CN1864359B

CN1864359B - Methods for seamless delivery of broadcast and multicast content across cell borders and/or between different transmission schemes and related apparatus

Info

Publication number: CN1864359B
Application number: CN2004800286925A
Authority: CN
Inventors: F·格里利; A·H·瓦亚诺斯; L·卡萨恰
Original assignee: Qualcomm Inc
Current assignee: Qualcomm Inc
Priority date: 2003-08-21
Filing date: 2004-08-20
Publication date: 2012-04-18
Anticipated expiration: 2024-08-20
Also published as: CN1864359A; CN1868157A; CN1868157B; CN1871804A; CN1871804B

Abstract

Transmission techniques are provided that improve service continuity and reduce interruptions in delivery of content that can be caused by transitions that occur when the User Equipment (UE) moves from one cell to the other, or when the delivery of content changes from a Point-to-Point (PTP) connection to a Point-to-Multipoint (PTM) connection in the same serving cell, and vice-versa. Such transmission techniques enable seamless delivery of content across cell borders and/or between different transmission schemes such as Point-to-Multipoint (PTM) and Point-to-Point (PTP). Mechanisms for adjusting different streams and for recovering content from each data block during such transitions are also provided so that data is not lost during a transition. In addition, mechanisms for realigning data during decoding at a receiving terminal are also provided.

Description

Be used to broadcast and multicast content across cell border and/or different transfer scheme between the method and the relevant apparatus of seamless delivery

Priority according to 35 U.S.C. §, 119 requirements

60/497 of " the Method and Apparatus forSeamless Delivery of Broadcast and Multicast Content Across Cell Bordersand/or Between Different Transmission Schemes " by name that the application requires to submit on August 21st, 2003; 60/497 of " the L2 Design for Outer Coding Scheme " by name that submits in No. 457 provisional application and on August 21st, 2003; The priority of No. 456 provisional application; They the two can be transferred its assignee, thereby can be at this as a reference with its specific reference.

Technical field

The present invention relates generally to communication system, and relates more specifically to broadcast the transmission with multicast content.

Background technology

Wireless communication system has been used to transmit the non-voice service of speech business and low data rate traditionally.Now, the wireless communication system that also transmits such as the business of high data rate (HDR) multimedia service of video, data and other type just is implemented.The stream that multimedia broadcasting and multicast services (MBMS) channel can be used for transmitting based on voice, Voice & Video data source is used, such as the audio or video content of radio broadcasting, television broadcasting, film and other type.Delay and a certain amount of loss or bit error can be tolerated in the flow data source, because these flow data sources are intermittent sometimes, and typically compress.In this regard, the transmit data rate of arrival wireless access network (RAN) possibly be extremely variable.Because the application layer buffering area typically is limited, so need to support the MBMS transmission mechanism of variable source data rate.

Typically, the base station offers subscriber station to this multimedia service service through launching the information signal that can be organized into a plurality of groupings usually.Grouping can be the one group of byte that is arranged in specific format that comprises data (payload) and control element.Control element can comprise for example preamble (preamble) and quality metric, and quality metric can comprise the tolerance of Cyclic Redundancy Check, parity check bit and other type.Divide into groups to be formatted into message usually according to communication channel structure.Message is propagated between initial terminal and purpose terminal, and can receive the influence of communication channel characteristics, becomes and the influence of other such characteristic such as receiving signal noise ratio, decline, time.In different communication channel, these characteristics can influence modulation signal differently.Wherein one is, the transmission of modulating information signal on radio communication channel needs to select appropriate method to protect the information in the modulation signal.These methods can comprise that for example coding, symbol repeat, interweave and the known additive method of those of ordinary skill in the art.Yet these methods have increased expense.Therefore, must between message transmission reliability and amount of overhead, make in the design compromise.

Typically, the operator selects point-to-point (PTP) connection or point-to-multipoint (PTM) to connect according to receiving the number of MBMS content users interest station or subscriber equipment (UE) by ground, sub-district.

Point-to-point (PTP) transmission uses dedicated channel to send to the selected user in the overlay area to service." special use " channel sends information the unique user station to or sends the information from the unique user station.In point-to-point (PTP) transmission, independent channel can be used for the transmission to each travelling carriage.Upwards be used for the private subscribers business that a user serves at forward link or downlink side, can transmit through the logic channel that for example is called Dedicated Traffic Channel (DTCH).For example, if in the overlay area, there is not the user of specific multimedia broadcasting of enough needs and multicast services (MBMS), then point-to-point (PTP) communication service typically is the most effective.Only send service under such situation of the specific user who asks this service in the base station, can use point-to-point (PTP) transmission.For example, in the WCDMA system, before the travelling carriage that has more than predetermined number, using dedicated channel or point-to-point (PTP) to transmit can be more effective.

" broadcast communication " or " point-to-multipoint (PTM) communication " is through the communication of common communication channel to a plurality of travelling carriages." public " channel sends information a plurality of subscriber stations to or sends the information from a plurality of subscriber stations, and can be used simultaneously by several terminals.In point-to-multipoint (PTM) communication service, if for example in the overlay area of base station, need the multimedia service service the user outnumber predetermined threshold number, then cellular basestation can be broadcasted this multimedia service service on common signal channel.In CDMA 2000 systems, broadcasting or point-to-multipoint (PTM) transmission typically replace PTP to transmit and use, because the PTM radio bearer is almost the same with the PTP radio bearer effective.From the common signal channel transmission of certain base station, can be unnecessary and synchronous from the common channel communication of other base station.In typical broadcast system, one or more central stations offer content (user's radio network).Central station can send information to all subscriber stations or one group of specific subscriber station.Each keeps watch on the common forward link signal to broadcast service users interest station.Point-to-multipoint (PTM) transmission can be sent on down link or forward common channels.Typically, common broadcast forward link signal is broadcasted on one-way channel, goes up broadcasting such as the CTCH Common Traffic Channel (CTCH) in being present in forward link or " down link " direction.Because this channel is unidirectional, thus subscriber station usually not with base station communication because allow all subscriber units, may make the communication system overload conversely to base station communication.Like this, under the background of point-to-multipoint (PTM) communication service, when in the information that receives at subscriber station error code being arranged, subscriber station may not be conversely to base station communication.Therefore, the out of Memory safeguard measure can be desirable.

In CDMA 2000 systems, subscriber station can soft combination in point-to-multipoint (PTM) transmission.Even when having taked measure to protect information signal, the situation of communication channel also may worsen, so that can not decode through some grouping of dedicated channel transmission in the point of destination.In these cases, a kind of method can be the automatic repeat requests (ARQ) of being stood and being made to initial (base station) station by purpose (user) through using, and comes to retransmit simply the grouping that can not decode.Re-transmission helps to guarantee the transmission of packet.If data can not be by correct transmission, then the user of the RLC of transmission end can obtain notice.

Typically, subscriber station can experience conversion in many cases.These are changed available different mode and classify.For example, conversion can be divided into " cross over transition " and " directly conversion ".Also conversion can be divided into " minizone " conversion and " in the sub-district " conversion.

Conversion between sub-district or the transfer scheme can cause the undesirable service disruption of user's possibility.When subscriber station or subscriber equipment (UE) when a sub-district moves to another, or when in the transmission of broadcasting of Serving cell inner multimedia and multicast services (MBMS) content when a kind of pattern becomes another kind of pattern, may go wrong.From the transmission of adjacent cell, the relative to each other time shift of the amount of having Δ t1.And, may introduce additional delay in the transition period, because travelling carriage need be confirmed the system information in the Target cell, this needs a certain amount of processing time Δ t2.Data flow from different districts (or point-to-point (PTP)/point-to-multipoint of different transmission channel kinds (PTM)) transmits relative to each other possibly have skew.Therefore, between point-to-multipoint (PTM) transmission period of different districts, travelling carriage may receive same content twice, and perhaps some piece content may be lost.This is not fully up to expectations aspect service quality.Between the sub-district and/or the conversion between point-to-point (PTP) transmission and point-to-multipoint (PTM) transmission, depend on the duration of conversion and transmit between delay or deviation, the interruption in can causing serving.

Therefore; Need to provide service continuity and the transmission technology that reduces the interruption in the content transmission in the art; Interruption during wherein content transmits can be caused by the conversion that takes place in the following moment: when subscriber equipment (UE) when a sub-district moves to another; Or connect when becoming point-to-multipoint (PTM) and connecting, and when the rightabout conversion of generation when the content in same Serving cell transmits from point-to-point (PTP).These transmission technologys will preferably can realize striding cell boarder and/or such as the seamless delivery of the content between the different transmission schemes between point-to-multipoint (PTM) and point-to-point (PTP).Be used for recovering the mechanism of content transition period, also expect, so that data can not lost in the transition period in these adjustment different data streams with from each data block.Be provided for during the decoding of receiving terminal the mechanism of array data again, also will expect.

Description of drawings

Fig. 1 is the figure of communication system;

Fig. 2 is the block diagram of UMTS signaling protocol stack;

Fig. 3 is the block diagram on the packet switching user plane of UMTS protocol stack;

Fig. 4 is the block diagram of the Access Layer part of UMTS signaling protocol stack;

Fig. 5 A is the block diagram of data-transmission mode that uses in Radio Link control (RLC) layer of UMTS signaling protocol stack and the various channels that in every layer, use;

Fig. 5 B is the block diagram that shows the structure of Radio Link control (RLC) layer that comprises various RLC data-transmission modes;

Fig. 5 C is the block diagram that shows the entity be used to realize Radio Link control (RLC) affirmation mode (AM);

Fig. 6 is improved block diagram with UMTS protocol stack of forward error correction layer;

Fig. 7 A has shown the embodiment of the protocol architecture of the Access Layer that comprises forward error correction (FEC) layer;

Fig. 7 B has shown another embodiment of the protocol architecture of the Access Layer that comprises forward error correction (FEC) layer;

Fig. 8 be block of information and with the block diagram of the corresponding external code piece of this block of information;

Fig. 9 A shows to may be used on the external code block structured block diagram in multimedia broadcasting and multicast services (MBMS) data;

Fig. 9 B is the external code block structured block diagram of displayed map 9A, and wherein every Transmission Time Interval (TTI) sends multirow;

Fig. 9 C is the external code block structured block diagram of displayed map 9A, and wherein every row is sent out in a plurality of TTI;

Figure 10 A and 10B are the block diagrams that shows the external code piece that is generated by the forward error correction layer;

Figure 11 is the embodiment of forward error correction (FEC) layer that uses in the RLC UM+ entity;

Figure 12 A has shown the encoding process that is used for generating from data cell the external code piece, and wherein the capable size of external code piece is fixed;

Figure 12 B has shown in Figure 12 A the instance through aerial emission information;

Figure 13 has shown the encoding process that is used to generate the external code piece with variable row size;

Figure 14 is the figure of the embodiment of forward error correction (FEC) form;

Figure 15 is used to make the travelling carriage can be the algorithm of the time migration between the decoding delay Different Logic stream;

Figure 16 shows when travelling carriage is being received from point-to-multipoint (PTM) transmission of sub-district A and between another point-to-multipoint (PTM) transmission of sub-district B, is changing, by the figure of the time relationship between the external code piece of travelling carriage reception;

When Figure 17 is the conversion generation that is presented between point-to-multipoint (PTM) transmission and point-to-point (PTP) transmission, by the figure of the time relationship between the external code piece of travelling carriage reception;

Figure 18 is presented at from radio network controller (RNC) A point-to-point (PTP) transmission with during the conversion between another point-to-point (PTP) of radio network controller (RNC) B transmission or reorientating, by the figure of the time relationship between the external code piece of travelling carriage reception.

Embodiment

Speech " schematically " is used to refer to " as example, instance or illustration " in this article.Any embodiment that describes as " schematically " in this article not necessarily is interpreted as preferred embodiment or more favourable than other embodiment.

Term " travelling carriage " can exchange with term " point of destination ", " subscriber station ", " subscriber unit ", " terminal " and " subscriber equipment (UE) " in this article and use; And be used to refer to hardware in this article; Such as the base station, this base station with communicate by letter such as the Access Network of UMTS Terrestrial radio access network (UTRAN).In the UMTS system, subscriber equipment (UE) is to allow the user to insert the device of UMTS network service, and preferably includes the USIM that comprises all consumer premise information.Travelling carriage can be that move or static, and can comprise usually through wireless channel or any communicator, data set or the terminal that communicate through the wire message way that for example uses optical fiber or coaxial cable.Travelling carriage can be implemented in such device, and this device comprises PC card, compact flash, outside or internal modems or mobile or fixed line telephone, but included parts are not in these parts.

Term " state is set up in connection " refers to such state, travelling carriage be in set up with processing that the active traffic channel of base station is connected in.

Term " service condition " refers to such state, and travelling carriage has and that set up is connected with the active traffic channel base station.

Term " communication channel " in this article based on context is used to refer to physical channel or logic channel.

Term " physical channel " is used to refer to the channel that transmits user data or control information through air interface in this article.Physical channel provides wireless platform " transmission medium ", and in fact information be transmitted through this wireless platform, and physical channel is used for transmitting signaling and user data through Radio Link.Typically, physical channel comprises the combination of scrambling code and channel code.On uplink direction, also can comprise relative phase.Just attempt the thing done based on travelling carriage, can on up link, use many different physical channels.In the UMTS system, the term physical channel can also refer to for the different types of bandwidth of different purpose through the Uu interface assignment.The physics that physical channel constitutes the Uu interface between subscriber equipment (UE) territory and the network insertion territory exists.Physical channel can define through physical mappings and the attribute that is used for transmitting through air interface data.

Term " transmission channel " is used to refer in this article, is used for the communication route of the transfer of data between the reciprocity physical layer entity.Transmission channel relates to the mode that information is transmitted.Usually, two types the transmission channel that is called Common transport channel and dedicated transmission channel can be arranged.Transmission channel can for example whether use special use or public physic channel, or logic channel be multiplexing by how can maybe can define through which type of performance data of the transmission of the air interface on the physical layer through the air interface transmission characteristic data on the physical layer.Transmission channel can be used as the Service Access Point (SAP) of physical layer.In the UMTS system, how transmission channel can transmit logic channel if being described, and be mapped to physical channel to these information flows.Transmission channel is used between medium access control (MAC) layer and the physical (L1) and transmits signaling and user data.Radio network controller (RNC) is checked transmission channel.Information passes to physical layer through in many transmission channels that can be mapped to physical channel any one from the MAC layer.

Term " logic channel " is used to refer to the information flow that the information that is specifically designed to particular type or wave point transmit in this article.Logic channel relates to the information that just is being transmitted.Can be that what type is come definition of logical channels through the information that is transmitted, for example can define, and can it be interpreted as the different task that network and terminal should be carried out in different time points by signaling or user data.Can be mapped to logic channel in the transmission channel of the actual information transmission of carrying out between travelling carriage territory and the input field.Information transmits via logic channel, and logic channel can be shone upon through the transmission channel that can be mapped to physical channel.

Term " dedicated channel " be used to refer in this article typically be specifically designed to the specific user or keep for the specific user and be sent to information specific travelling carriage, subscriber unit or user's set or send channel from the information of specific travelling carriage, subscriber unit or user's set.Typically, dedicated channel transmits plans to mail to the information that given user uses, and this information comprises data and the higher level control information that is used for active service.Dedicated channel can be by the certain code identification on the certain frequency.Dedicated channel can be two-way, to be convenient to feedback potentially.

Term " common signal channel " is used to refer in this article and sends information a plurality of travelling carriages to or send the transmission of Information channel from a plurality of travelling carriages.In common signal channel, information can be shared in all travelling carriages.Can divide common signal channel between all users or between one group of user in a sub-district.

Term " point-to-point (PTP) communication " is used to refer to the communication that is sent to single mobile station through special-purpose physical communication channels in this article.

Term " broadcast communication " or " point-to-multipoint (PTM) communication " can be used to refer to through the communication of common communication channel to a plurality of travelling carriages in this article.

Term " reverse link or uplink channel " is used to refer to communication channel/link in this article, and through this communication channel/link, travelling carriage sends to the base station to signal in wireless access network.This channel also can be used for sending the signal from travelling carriage to mobile base station, or sends the signal from the mobile base station to base station.

Term " forward link or downlink channel " is used to refer to communication channel/link in this article, and through this communication channel/link, wireless access network sends to travelling carriage to signal.

Term " Transmission Time Interval (TTI) " is used to refer to data in this article and how long arrives physical layer once from higher level.Transmission Time Interval (TTI) can refer to the blanking time that transmission block collection (TBS) arrives, and is approximately equal to the cycle that TBS is transmitted by the physical layer on the wave point.In the data that on transmission channel, transmit during the TTI, can be encoded and weave in.The sustainable a plurality of radio frames of TTI, and can be interweave many times of cycle of minimum.Can be the original position of the TTI of single connection multiplexing different transmission channels together, is time alignment.TTI has public starting point.The every TTI of medium access control just is transferred to physical layer to a transmission block collection.Be mapped in the different transmission channels on the same physical channel, can have different Transmission Time Intervals (TTI) duration.Can in a TTI, transmit a plurality of PDU.

Term " grouping " is used to refer to the one group of bit that is arranged in specific format that comprises data or payload and control element in this article.Control element can comprise for example preamble, quality metric and other control element as well known to those skilled in the art.Quality metric comprises, for example Cyclic Redundancy Check, parity check bit and other quality metric as well known to those skilled in the art.

Term " Access Network " is used to refer in this article and is used for the necessary equipment of access network.Access Network can comprise the set or the network of base station (BS) and one or more base station controller (BSC).Access Network transmits packet between a plurality of subscriber stations.Access Network can further be connected to the other network beyond the Access Network, such as Intranet or internet, and can access terminal and this external network between transmit packet.In the UMTS system, can call UMTS Terrestrial radio access network (UTRAN) to Access Network.

Term " core net " is used to refer in this article and is used to the circuit-switched call in circuit switching (CS) territory and is connected to PSTN (PSTN), or is connected to the exchange and the routing capability of packet data network (PSDN) for the packet switched call in packet switching (PS) territory.The routing capability that term " core net " also refers to be used for mobility and customer location management and is used for authentication service.Core net is included as exchange and the user controls needed network element.

Term " base station " is used to refer to " initiating station " in this article, should " initiating station " comprise the hardware that travelling carriage is communicated by letter with it.In the UMTS system, term " Node B " can exchange with term " base station " and use.The base station can be that fix or mobile.

Term " sub-district " depends on the context that uses this term in this article, is used to refer to hardware or geographical coverage area.

Term " service data unit (SDU) " is used to refer in this article, be positioned at the data cell of agreement exchange of agreement interested top.

Term " payload data unit (PDU) " is used to refer in this article, be positioned at the data cell of agreement exchange of agreement interested below.If the sign of agreement interested indeterminate, then will in title, mention clearly.For example, FEC-PDU is the PDU of FEC layer.

Term " soft handover " is used to refer to the communication between subscriber station and two or more sectors in this article, and wherein each sector belongs to different sub-districts.Reverse link communication can be received by two sectors, and forward-link communication can be transmitted on the forward link of two or more sectors simultaneously.

Term " softer handover " is used to refer to the communication between subscriber station and two or more sectors in this article, and wherein each sector belongs to identical sub-district.Reverse link communication can be received by two sectors, and forward-link communication is transmitted in the forward link of two or more sectors simultaneously.

Term " deletion " is used to refer in this article can not identification message, also can be used to refer to the sets of bits that when decoding, can lose.

Term " cross over transition " may be defined as, and is transferred to the conversion that point-to-multipoint (PTM) is transmitted from point-to-point (PTP), or rightabout conversion.Four kinds of possible cross over transition are: point-to-point (PTP) from the A of sub-district is transferred to the conversion of point-to-multipoint (PTM) transmission among the B of sub-district; Point-to-multipoint from the A of sub-district (PTM) is transferred to the conversion of point-to-point (PTP) transmission among the B of sub-district; Point-to-point (PTP) from the A of sub-district is transferred to the conversion of point-to-multipoint (PTM) transmission among the A of sub-district, and the point-to-multipoint from the A of sub-district (PTM) is transferred to the conversion of point-to-point (PTP) transmission among the A of sub-district.

Term " directly conversion " may be defined as, the conversion from a point-to-point transmission to another point-to-point transmission and be sent to the conversion of point-to-multipoint transmission from point-to-multipoint.Two kinds of possible direct conversions are, the conversion of conversion of point-to-point (PTP) transmission in the B of sub-district of point-to-point (PTP) from the A of sub-district and the point-to-multipoint from the A of sub-district (PTM) point-to-multipoint (PTM) transmission in the B of sub-district.

Term " inter-cell transitions " is used to refer to the conversion of striding cell boarder.Four kinds of possible inter-cell transitions are: point-to-point (PTP) from the A of sub-district is transferred to the conversion of point-to-point (PTP) transmission among the B of sub-district; Point-to-multipoint from the A of sub-district (PTM) is transferred to the conversion of point-to-multipoint (PTM) transmission among the B of sub-district; Point-to-point (PTP) from the A of sub-district is transferred to the conversion of point-to-multipoint (PTM) transmission among the B of sub-district and the conversion that the point-to-multipoint from the A of sub-district (PTM) is sent to point-to-point (PTP) transmission among the B of sub-district.Usually, the most frequent conversion is that the point-to-multipoint (PTM) of striding cell boarder is transferred to the conversion that point-to-multipoint (PTM) is transmitted.

Term " sub-district internal conversion " is used to refer to the conversion from a kind of pattern to another kind of pattern in the sub-district.Two kinds of possible sub-district internal conversions are: point-to-point (PTP) from the A of sub-district is transferred to the conversion of point-to-multipoint (PTM) transmission among the A of sub-district and the conversion that the point-to-multipoint from the A of sub-district (PTM) is transferred to point-to-point (PTP) transmission among the A of sub-district.

Term " radio bearer " is used to refer to, the service that the layer 2 that is transmitted by the user data that is used between subscriber equipment (UE) and the UMTS Terrestrial radio access network (UTRAN) is provided.

Now embodiments of the invention will be discussed, be implemented in WCDMA or the UMTS communication system aspect discussing above in these embodiment.Fig. 1-5C has explained some aspects of traditional UMTS or WCDMA system, and that wherein describes in this article can be applicable to this aspect of the present invention in describing, and has been merely the purpose of explanation and restriction and is provided.Be understood that; Aspect of the present invention also can be applicable to and not only transmits voice but also transmit in other system of data; Such as gsm system that meets following standard and CDMA 2000 systems: be embodied in the group file that comprises 3G TS25.211,3G TS 25.212,3G TS 25.213 and 3G TS 25.214 (W-CDMAB standard) number file " third generation partner program " (3GPP), or " the TR-45.5 physical layer standard that is used for the cdma2000 spread spectrum system " (IS-2000 standard) and such as the GSM standard of TS 04.08 (mobile wireless interface layer 3 standards), TS 05.08 (wireless subsystem controlling links) and TS 05.01 (physical layer on the wireless path (describe, in general terms)).

For example; Indicate although describe; Wireless access network 20 can realize through using universal land radio access web (UTRAN) air interface, but alternatively, in the GSM/GPRS system; Access Network 20 can be GSM EDGE Radio Access Network (GERAN), or it can comprise the sub-district of UTRAN air interface and the sub-district of GSM/EDGE air interface under the situation between system.

UMTS network topology

Fig. 1 is the block diagram according to the communication system of UMTS network topology.The UMTS system comprises subscriber equipment (UE) 10, Access Network 20 and core net 30.UE 10 is connected to Access Network, and Access Network is connected to core net 30, and core net 30 can be connected to external network.

UE 10 comprises mobile unit 12 and the USIM (USIM) 14 that comprises consumer premise information.(unshowned) Cu interface is the electrical interface between USIM 14 and the mobile unit 12.UE 10 normally allows the user to insert the device of UMTS network service.UE10 can be such as cellular wheeled apparatus, fixed station, or other data terminal.Mobile unit can be the wireless terminal that for example is used for carrying out through air interface (Uu) radio communication.The Uu interface is such interface, and UE is through the standing part of this interface connecting system.USIM normally is installed in the application program on the logic card that " smart card " or other comprise microprocessor.Smart card is preserved CUSTOMER ID, carries out identifying algorithm, and authentication store in encryption key and user profile that the terminal needs.

Access Network 20 comprises the wireless device that is used for access network.In the WCDMA system, Access Network 20 is universal land radio access web (UTRAN) air interfaces.UTRAN comprises at least one RNS (RNS), and this RNS comprises at least one base station or " Node B " 22 that is connected at least one radio network controller (RNC) 24.

The Radio Resource of RNC control UTRAN.The RNC 24 of Access Network 20 communicates by letter with core net 30 through the Iu interface.Uu interface, Iu interface 25, Iub interface and Iur interface allow from the internetworking between the equipment of different manufacturers, and in the 3GPP standard, are specified.The realization of radio network controller (RNC) changes with the difference of producer, therefore will describe with generic term below.

Radio network controller (RNC) 24 is used as the exchange and the control element of UMTS Terrestrial radio access network (UTRAN), and between Iub interface and Iu interface 25.RNC for example for managing the connection of subscriber equipment, serves as Service Access Point for offered all services of core net 30 by UTRAN.Iub interface 23 connected node B 22 and radio network controller (RNC) 24.The Iu interface is connected to core net to UTRAN.Radio network controller (RNC) provides the switching point between Iu carrying and the base station.Subscriber equipment (UE) 10 can have several radio bearers it self and radio network controller (RNC) between 24.This radio bearer relates to subscriber equipment (UE) border (contex), and this border, user field is that Iub is connected and one group of definition of needs with special-purpose in order to arrange the public connection between subscriber equipment (UE) and the radio network controller (RNC).Corresponding RNC 24 can be through the optional Iur interface of the soft handover between the sub-district that allows to be connected to different nodes 22, intercommunication mutually.Like this, the Iur interface allows the connection between RNC.In these cases, when Drift Radio Network Controller through one or more base stations 22, the frame that can exchange through the Iur interface, when sending travelling carriage 10 to, the Iu that Serving RNC is maintained to core net 30 connects 25, and execution selector and exterior ring power controlled function.

Can call the control RNC of Node B to the RNC of a Node B 22 of control, its controls the load of himself sub-district and congested, also carries out for the new Radio Link that in those sub-districts, will be established and admits control routine to distribute.

RNC and base station (or Node B) can be connected and communicate by letter via Iub interface 23.Each is connected to the use of the 22 pairs of Radio Resources in base station of specific RNC 24 RNC control.One or more sub-districts are controlled in each base station 22, and offer travelling carriage 10 to Radio Link.But the base station executive's interface is handled, such as chnnel coding with interweave rate adapted and expansion.Basic radio resource management operations is also carried out in the base station, controls such as inner loop power.Base station 22 conversion Iub and Uu interface 23, the data flow between 26.RRM is also participated in base station 22.Air interface Uu26 is connected to travelling carriage 10 to each base station 22.The wireless transmit of travelling carriage 10 can be responsible in one or more sub-districts in the base station, and can be responsible in one or more sub-districts the wireless receiving from travelling carriage 10.

Core net 30 comprises all following exchange and routing capabilities: (1) if current be circuit-switched call; Then be connected to PSTN 42, if perhaps current be packet switched call, then be connected to packet data network (PDN); (2) management of mobility and customer location and (3) authentication service.Core net 30 can comprise attaching position register (HLR) 32; Move Switching Service center/Visited Location Registor (MSC/VLR) 34; GMSC (GMSC) 36, service universal grouping wireless serving GPRS support node (SGSN) 38, and Gateway GPRS Support Node (GGSN) 40.

Can core net 30 be connected to external circuit exchange (CS) network 42 that provides circuit switching to connect; Such as current be PSTN (PSTN) or (ISDN) under the packet switched call situation; Perhaps can core net 30 be connected to PS network 44, such as current be the internet that is provided for the connection of packet data service under the situation of packet switched call.

The UMTS signaling protocol stack

Fig. 2 is the block diagram of UMTS signaling protocol stack 110.UMTS signaling protocol stack 110 comprises Access Layer and Non-Access Stratum (NAS).

Typically, Access Layer comprises physical layer 120, layer 2130 and Radio Resource control (RRC) layer 160, and its middle level 2130 comprises medium access control (MAC) layer 140 and Radio Link control (RLC) layer 150.Below, with each layer of describing Access Layer in more detail.

The UMTS Non-Access Stratum is identical with the GSM upper strata in fact, and can be divided into circuit switching part 170 and packet switched portion 180.Circuit switching part 170 comprises connection management (CM) layer 172 and mobile management (MM) layer 178.The 172 treatment circuit switched call of CM layer, and comprise each Seed Layer.Calling out control (CC) sublayer 174 carries out such as the function of setting up and discharging.The function that carry out such as Call Forwarding and Three-Way Calling supplemental services (SS) sublayer 176.Short Message Service is carried out in Short Message Service (SMS) sublayer 177.MM layer 178 is handled the position for circuit-switched call and is upgraded and authentication.Packet switched portion 180 comprises session management (SM) sublayer 182 and GPRS Mobility Management (GMM) sublayer 184.Session management (SM) sublayer 182 is handled packet switched call, and can be comprised Short Message Service (SMS) part 183 through carrying out such as the function of setting up and discharging.GMM sublayer 184 is handled the position for packet switched call and is upgraded and authentication.

Fig. 3 is the block diagram on the packet switching user plane of UMTS protocol stack.This stack comprises Access Layer (AS) and Non-Access Stratum (NAS).The NAS layer comprises application layer 80 and packet data protocol (PDP) layer 90.Application layer 80 is provided between subscriber equipment (UE) 10 and the long-distance user 42.Such as the PDP layer 90 of IP or PPP, be provided at GGSN 40 and subscriber equipment (UE) between 10.Low layer packet oriented protocol (LLPP) 39 is provided between long-distance user 42 and the SGSN 38.Iu interface protocol 25 is provided between radio network controller (RNC) 24 and the SGSN 38, and the Iub interface agreement is provided between radio network controller (RNC) 24 and the Node B 22.Other part of AS layer will be described below.

Access Layer (AS)

Fig. 4 is the block diagram of the Access Layer part of UMTS signaling protocol stack.The tradition Access Layer comprises physical (L1) 120, data link layer (L2) 130, Radio Link control (RLC) layer 150, PDCP (PDCP) layer 156, broadcast/group broadcast control (BMC) layer 158 and Radio Resource control (RRC) layer 160, and wherein data link layer (L2) 130 has the sublayer that comprises medium access control (MAC) layer 140.To further describe these layers below.

Radio bearer transmits user data 163 in application layer and layer 2 (L2) between 130.Control plane signaling 161 can be used for all UMTS dedicated control signaling, and comprises the application protocol of the signaling bear that is used for transmitting application protocol message.Application protocol can be used for setting up carrying to UE 10.All user plane information 163 of being sent and being received by the user of user-plane transmissions are such as the grouping in encoded voice in the audio call or the internet connection.User plane information 163 transmits data flow and the Data-carrying that is used for those data flow.Each data flow can be characterized for the Frame Protocol of that interface appointment by one or more.

Radio Resource control (RRC) layer 160 is as the master controller of Access Layer, and all other layers in the configuration Access Layer.Rrc layer 160 generates control plane signaling 161, and control plane signaling 161 is controlled Radio Link control unit 152, physical (L1) 120, medium access control (MAC) layer 140, Radio Link control (RRC) layer 150, PDCP (PDCP) layer 156 and broadcast/group broadcast control (BMC) layer 158.The type of Radio Resource control (RRC) layer 160 definite measurement of being done, and report those measurement results.Rrc layer 160 is also with control and the signaling interface of accomplishing Non-Access Stratum.

More specifically, rrc layer 160 is broadcast to all subscriber equipmenies (UE) 10 to the system information that comprises Access Layer and Non-Access Stratum cell.The Radio Resource control (RRC) that rrc layer 160 is set up, keeps and discharged between UTRAN 20 and the UE 10 connects.UE RRC asks to connect, and UTRAN RRC foundation is connected with discharging.The radio bearer between UTRAN 20 and the UE 10 is also set up, reshuffles and discharged to rrc layer 160, and start these operations through UTRAN 20.

Rrc layer 160 is process user equipment (UE) 10 ambulant each side also.These processes depend on the UE state, and calling is Circuit-switched or the calling of packet switching, and the wireless access technology (RAT) of new sub-district.Rrc layer 160 is paging UE 10 also.UTRAN RRC paging UE, and no matter UE whether at listening paging channel or Page Indication Channel.The upper strata of the RRC notice core net (CN) 30 of UE.

Data link layer (L2) 130 comprises medium access control (MAC) sublayer 40, Radio Link control (RLC) sublayer 150, PDCP (PDCP) sublayer 156 and broadcast/group broadcast control (BMC) sublayer 158.

Broadcasting and multicast control protocol (BMC) 158 come to transmit the message from CBC via wave point through on wave point with from the broadcast/multicast service of broadcast domain, adapting.BMC agreement 158 provides the service that is called " radio bearer ", and is present in the user plane.BMC agreement 158 and RNC store the cell broadcast messages through the CBC-RNC interface reception of the transmission that is used to be scheduled.At the UTRAN end, BMC 158 be calculated as the needed transmission rate of cell broadcast service based on passing through the message that (unshowned) CBC-RNC interface receives, and from the suitable CTCH/FACH resource of RRC request.BMC agreement 158 also through the CBC-RNC interface, receives schedule information together with each cell broadcast messages.Based on this schedule information, on the UTRAN end, BMC generates scheduling message, thereby generates scheduling BMC message sequence.On the subscriber equipment end, BMC estimates scheduling message, and indicates scheduling parameter to RRC, and this RRC can use these scheduling parameter to dispose the lower level that is used for discontinuous reception then.BMC also transmits BMC message, such as scheduling with according to the cell broadcast messages of dispatching.The cell broadcast messages of non-damage can be sent to the upper strata.Part control signaling Radio Resource control (RRC) 160 message between UE 10 and the UTRAN 20, this radio resource control information can be transmitted as foundation, revises and discharge layer 2 protocol 130 and needed all parameters of layer 1 agreement, 120 entity.RRC message transmits all higher level signalings in their payload.Radio Resource control (RRC) is through the signaling such as measurement, handover and cell update, and control is in the mobility of user equipment in the connection mode.

PDCP (PDCP) 156 is present in the user plane that is used for from the service in PS territory.Can call radio bearer to the service that provides by PDCP.PDCP (PDCP) provides letter head compression service.PDCP (PDCP) 156 includes compression method, and these compression methods can provide better spectrum efficiency for the service that transmits the IP grouping through radio.Can use any one in several letter header compression algorithms.PDCP is transmitting compression redundancy protocol information on the entity, and these information decompress on receiving entity.The letter head compression method can be exclusively used in particular network layer, transport layer or the for example upper-layer protocol combination of TCP/IP and RTP/UDP/IP.PDCP also transmits the user data that it receives from Non-Access Stratum with the form of PDCP service data unit (SDU), and gives the RLC entity these data forwarding, and vice versa.PDCP also provides support for harmless SRNS reorientates.When PDCP uses affirmation mode (AM) RLC to transmit according to the order of sequence; Can be configured to support can't harm the PDCP entity that RSRNS reorientates; Has protocol Data Unit (PDU) sequence number; These protocol Data Unit sequence numbers can be divided into groups together with unacknowledged PDCP during reorientating, and are forwarded to new SRNC together.

Rlc layer 150 is through offering higher level (for example Non-Access Stratum) to service by the Service Access Point (SAP) of the IURNAP agreement use in higher level protocol in the UE end and the UTRAN end.Service Access Point (SAPS) is described how process data packets of rlc layer.Can be encapsulated in all higher level signalings in the RLC message, to be used for the transmission of wave point such as mobile management, calling control, session management etc.Rlc layer 150 comprises various radio link control entities 152, and these radio link control entities 152 are connected to MAC layer 140 through the logic channel that transmits signaling information and user data.

On control plane 161, the RLC service can be used to be used for the signaling transmission by rlc layer.On user plane 163, RLC service can be by using with special services protocol layer PDCP or BMC, or can be used by other higher level user-plane function.For the service of not using PDCP 156 or user-plane protocol, in control plane 161, can the RLC service be called Signaling Radio Bearer, in user plane 163, can be referred to as radio bearer.In other words, if service can not be used PDCP and BMC agreement, then rlc layer 150 provides the service that is called Signaling Radio Bearer (SRB) in control plane 161, and the service that is called radio bearer (RB) is provided in user plane 163.Otherwise the RB service can be provided by PDCP layer 156 or BMC layer 158.

150 couples of user of Radio Link control (RLC) layer and control data execution framing function, this framing function comprises segmentation/splice and fills functional.Typically, rlc layer 150 offers Radio Resource control (RRC) 160 layers of the control data that is used for control plane 161 with segmentation and retransmission service, and offers the application layer of the user data that is used for user plane 163.Typically, rlc layer is segmented into less rlc protocol data cell (PDU) to the higher layer protocol data units of variable-length (PDU) and from the higher layer protocol data units (PDU) of less rlc protocol data cell (PDU) reorganization variable-length.Typically, Radio Link control (RLC) protocol Data Unit (PDU) transmits a PDU.For example, can the size of Radio Link control (RLC) PDU be set according to the minimum possibility bit rate of the service that is used to use Radio Link to control (RLC).Like what below will discuss,, when use is higher than any bit rate of lowest bit rate, during a Transmission Time Interval (TTI), can transmit several Radio Link control (RLC) PDU for variable rate services.RLC transmits entity and also carries out splicing.If the content of Radio Link control (RLC) service data unit (SDU) is not filled integer Radio Link control (RLC) PDU; Then can be put into first section of next Radio Link control (RLC) SDU among Radio Link control (RLC) PDU, with the final stage splicing of previous RLC SDU.Typically, RLC transmits entity and also carries out the filling function.When remaining when the data that are transmitted are not filled whole Radio Link control (RLC) PDU to sizing, the remainder of that data field, available filling bit is full of.For example, according to the following aspect of discussing with reference to Figure 11-13 of the present invention, can be provided for reducing or eliminating the technology of employed loading.

The RLC receiving entity detects the repetition of Radio Link control (RLC) PDU that receives, and guarantees that the result among the higher level PDU is transmitted to the upper strata once.Rlc layer is also controlled PRLC and is transmitted the speed that entity can send to information the RLC receiving entity.

Fig. 5 A is the block diagram of explanation data-transmission mode of use in Radio Link control (RLC) layer of UMTS signaling protocol stack, the figure illustrates the possible mapping with respect to Access Layer of logic, transmission and physics UMTS channel.What those skilled in the art may appreciate that is, for given subscriber equipment (UE), all mappings will not necessarily be defined at synchronization, and a plurality of instances of some mappings can take place simultaneously.For example, audio call can use three Dedicated Traffic Channels (DTCH) logic channel that is mapped to three dedicated channels (DCH) transmission channel.And some channels that show among Fig. 5 such as CPICH, SCH, DPCCH, AICH and PICH, are present in the physical layer background, and do not transmit top signaling or user data.Can define the content of these channels at physical layer 120 (L1).

Each RLC instance in Radio Link control (RLC) layer can be controlled (RRC) layer 160 by Radio Resource and be configured to, and operates in the pattern in following three kinds of patterns: transparent mode (TM), Unacknowledged Mode (UM) or affirmation mode (AM).To be discussed in more detail below them with reference to Fig. 5 B.Three kinds of data-transmission modes indicate the pattern that Radio Link control (RLC) is configured for logic channel.Transparent and Unacknowledged Mode RLC entity is defined by unidirectional, and the affirmation mode entity is two-way.Usually, for all RLC patterns, crc error detects and on physical layer, is performed, and the result of CRC check, is transmitted to RLC together with real data.According to the particular requirement of each pattern, these patterns are carried out the some or all of functions of rlc layer 150, comprise segmentation, reorganization, splicing, filling, re-transmission control, current control, duplicate detection, transmission according to the order of sequence, error correction and encryption.To be described in greater detail below these functions with reference to Fig. 5 B and 5C.According to aspect this discussion of the present invention, a kind of new Radio Link control (RLC) data-transmission mode can be provided.

MAC layer 140 offers rlc layer 150 to service through by the logic channel that type of data characterized that transmits.Medium access control (MAC) layer 140 is the logic channel mapping and be multiplexed into transmission channel.Subscriber equipment (UE) on the MAC layer 140 identification common signal channel.MAC layer 140 also is multiplexed into higher level PDU in the transmission block that is transmitted to the physical layer on the Common transport channel, and the transmission block that sends the physical layer from Common transport channel demultiplexes into higher level PDU.MAC handles the service multiplexing that is used for Common transport channel, because this can not carry out in physical layer.When Common transport channel sent the data from special-purpose type logic channel, medium access control (MAC) letter head comprised the sign of UE.The MAC layer also is multiplexed into higher level PDU in the transport block set that is transmitted to the physical layer on the dedicated transmission channel, or the transport block set that sends the physical layer from dedicated transmission channel demultiplexes into higher level PDU.

MAC layer 140 is with RLC PDU, and the state information together with transmit the data volume in the buffer about RLC receives together.MAC layer 140 handle and the corresponding data volume of transmission channel are with the threshold of rrc layer 160 settings.If data volume is too high or too low, then MAC sends to RRC to the measurement report about the traffic carrying capacity state.Rrc layer 160 also can ask MAC layer 160 periodically to send these measurement results.Rrc layer 160 uses these reports, triggers reconfiguring of radio bearer and/or transmission channel.

The MAC layer also depends on the instantaneous source speed of logic channel, for each transmission channel is selected suitable transformat (TF).MAC layer 140 provides the processed of data flow through selecting " bit rate " and " low bit speed rate " transformat (TF) for different data flow.Packet switching (PS) data are paroxysmal inherently, and the amount of the data that therefore can be used for sending changes with the difference of frame.But as the more data time spent, MAC layer 140 can be selected in the high data rate more, yet but when signaling and user data time spent all, MAC layer 140 is selected between them, so that the amount maximum of the data of sending from high priority channel more.Can select transformat (TF) with respect to being controlled to be the transformat combination (TFC) that each connects definition by admittance.

Medium access control (MAC) layer is also carried out and is encrypted.Can encrypt each radio bearer respectively.The details of encrypting is described among the 3GPP TS 33.102.

In system such as WCDMA, have three types can be used for transmitting the transmission of packet data channel.These channels are usually said Common transport channel, dedicated transmission channel and shared transmission channels.In down link, the transmission channel grouped data is selected by packet scheduling algorithm.In up link, transmission channel is selected based on the parameter of packet scheduling algorithm setting by wheeled apparatus 10.

Common signal channel can be for example the RACH RACH in the up link and the forward access channel FACH in the down link.They all transmit signaling data and user data.Common signal channel has low settling time.Because common signal channel can be used for sending signal before connecting foundation, so can being used for sending at once, common signal channel divides into groups, and very not long settling time.Typically, there are several RACH or FACH in each sector.Common signal channel does not have feedback channel, therefore typically uses open Loop Power control or constant power.And common signal channel can not use soft handover.Therefore, the junctor level performance of common signal channel can be than the junctor level poor performance of dedicated channel, and can produce more the interference than dedicated channel.Therefore, common signal channel can be more suitable for transmitting little single grouping.The application of in common signal channel, using will be the application such as Short Message Service and short text mail.Send to webpage to single request, also meet very much the notion of common signal channel, but under the situation of larger data amount, the wireless performance that common signal channel is differed from.

Dedicated channel can be used fast power control and the soft handover characteristic of improving wireless performance, and typically, produces interference still less than common signal channel.Yet, set up dedicated channel than inserting common signal channel cost more time.Dedicated channel can have from the variable bit-rate of several kilobytes per seconds up to 2 megabyte per seconds.Because bit rate changes during the transmission, so must be according to bit rate allocation of downlink orthogonal code.Therefore, the variable bit-rate dedicated channel consumes valuable down link orthogonal code space.

Physical (L1) 120 is connected to MAC layer 140 through transmitting the transmission channel of signaling information and user data.Physical layer 120 through can by how the transmission characteristic data with transmit the transmission channel which type of performance data characterizes, offer the MAC layer to service.

Physical (L1) 120 receives signaling and user data on the Radio Link through physical channel.Typically; Physical (L1) is carried out multiplexing and is comprised chnnel coding, forward error correction (FEC), rate-matched, interlaced transmission channels data and the multiplexing transmission information channel data that CRC calculates; And other physical layer procedure, such as obtain, access, paging and Radio Link foundation/failure.Physical (L1) also can be responsible for spread spectrum and scrambling, modulation, measurement, transmission divides collection, power weightings, handover, compact model and power control.

Fig. 5 B is the block diagram of the structure of display radio controlling links (RLC) layer.As mentioned above; Each RLC entity in Radio Link control (RLC) layer 150 or instance 152 can be controlled (RRC) layer 160 by Radio Resource and be configured to, and operate in the pattern in following three kinds of data-transmission modes: transparent mode (TM), Unacknowledged Mode (UM) or affirmation mode (AM).Service quality (OoS) is provided with the data-transmission mode that may command is used for user data.

TM is unidirectional, and comprises transmission TM entity 152A and receive TM entity 152B.In transparent mode, there is not agreement to be added in the higher-layer data in proper order.The protocol Data Unit of discardable mistake (PDU) or it is designated as wrong.Higher-layer data typically not by the situation of segmentation under, can use stream transmission,, can realize the transmission of limited segmentation/reorganization ability although under specific circumstances.When using segmentation/reorganization, can set up in the process at radio bearer and consult.

UM also is unidirectional, and comprises transmission UM entity 152C and receive UM entity 152D.UM RLC entity is defined as unidirectional, because do not need the contact between up link and the down link.Do not guarantee that in UM data transmit.UM can be used for for example certain RRC signaling procedure, and in this process, confirming and retransmitting is not the part of RRC process.Use the instance of user's service of Unacknowledged Mode RLC to be, cell broadcast service and the voice through IP.According to configuration, but the misdata that mark receives or it is abandoned.Can use do not have the explicit signaling function based on the abandoning of timer, like this, can be simply the RLCPDU that transmits in can not be at the appointed time, from transmit buffer, remove.In non-affirmation data-transmission mode, the PDU structure comprises sequence number, and can carry out the sequence number verification.When the sequence number verification is controlled among (RLC) SDU through being recombined to Radio Link at Radio Link control (RLC) PDU; Sequence number among verification Radio Link control (RLC) PDU; Help to guarantee the integrality of the PDU that recombinates and the means that detect Radio Link control (RLC) SDU that damages are provided.Can abandon Radio Link control (RLC) SDU of any damage.In Unacknowledged Mode (UM), also segmentation and splicing can be provided.

In affirmation mode, RLC AM entity is two-way, and can be the indication of Link State incidentally in reciprocal user data.Fig. 5 C shows the block diagram that is used to realize the entity of Radio Link control (RLC) affirmation mode (AM) entity and how can constructs AM PDU.From the packet (RLC SDU) that higher level receives, can and/or splice the protocol Data Unit (PDU) of 514 one-tenth regular lengths via AM-SAP by segmentation.The length of protocol Data Unit is the semi-static value that in the foundation of radio bearer, is determined, and can reconfigure process change through the RRC radio bearer.In order to splice or to fill purpose, can be inserted into the bit that is loaded with about length and extend information in the beginning part of last protocol Data Unit, perhaps comprise data from SDU.If several SDU can put into a PDU, then can they be spliced.Can insert suitable length indicator (LI) in the beginning part of PDU.Then, can be placed on PDU and transmit in the buffer 520, this transmission buffer is also safeguarded retransmission management.

Can construct PDU through following mode: get a PDU from transmitting buffer 520,,, then can add fill field or add status message incidentally if the data among the PDU are not full of whole RLC PDU for it adds the letter head.Status message incidentally can be from receiving terminal or from transmitting terminal, to indicate abandoning of RLCSDU.Letter head comprises RLC PDU sequence number (SN), can be used for from the poll bit (P) of peer-entities solicited status and optional length indicator (LI), if SDU splicing, filling or PDU have incidentally taken place in RLC PDU, then can use this length indicator.

Typically, affirmation mode (AM) is used for the service of packet type, downloads such as internet browsing and mail.In affirmation mode, repetitive requests (ARQ) mechanism can be used for error correction automatically.Any grouping with error code that receives can be retransmitted.The performance of the quality of RLC to postponing can be controlled by many re-transmissions that RLC provides through configuration by RRC.If RLC can not correctly transmit data, for example,, perhaps surpassed the re-transmission time if reached the maximum number of re-transmission, then notify the upper strata, and discardable this Radio Link control (RLC) SDU.Also can be through in status message, sending the movably receiving window order, come SDU abandon the operational notification peer-entities belong to the PDU that the Radio Link that is dropped is controlled (RLC) SDU so that receiver also removes all.

Both can be to transmit according to the order of sequence and also can be unordered (out-of-sequence) transmission configuration RLC.Through transmitting according to the order of sequence, can keep the order of the PDU of higher level, and the in a single day complete higher level PDU that receives of unordered transmission just sends them.Rlc layer provides the transmission according to the order of sequence of higher level PDU.This function has kept being submitted to the order of the higher level PDU that transmits for RLC.If do not use this function, then unordered transmission can be provided.Except data PDU transmitted, state and replacement control procedure can be sent with signal between reciprocity RLC entity.Control procedure even can use the logic channel that separates, like this, an AM RLC entity can use one or two logic channel.

In rlc layer, can be and confirm and non-affirmation RLC pattern execution encryption.In Fig. 5 C, except comprising PDU sequence number and poll bit two front two, AM RLC PDU encrypted 540.The PDU sequence number is an input parameter of AES, and must be able to be read by peer-entities, encrypts to carry out.3GPP standard TS33.102 has described encryption.

Then, can be transmitted to MAC layer 140 to PDU via logic channel.In Fig. 5 C, extra logic channel (DCCH/DTCH) with dashed lines shows that explanation can become a RLC physical arrangements, uses the different logical channel to send control PDU and data PDU.The receiving terminal 530 of AM entity receives RLC AMPDU through one in the logic channel from the MAC layer.The physical layer CRC that available energy is calculated on whole RLC PDU comes the verification error code.Actual CRC check can be carried out in physical layer, and the RLC entity data of result after together with whole letter epicranium deciphering that receive CRC check, and possible state information incidentally can be extracted from RLC PDU.If the PDU that receives is healthy and strong message, if perhaps state information then can be passed to transmitting terminal to control information (status message) by incidentally in AM PDU, the state information that the transmitting terminal contrast receives is checked its re-transmission buffer.PDU numbering from RLC letter head is used to decipher 550, and when storing into the PDU that encrypts in the reception buffer, the PDU sequence number also is used.In case all PDU that belong to complete SDU are in reception buffer the time, SDU just can recombinate.Although do not illustrate, before RLC SDU is sent to higher level, can be and transmit according to the order of sequence and duplicate detection execution verification.

When subscriber equipment (UE) or travelling carriage mobile between PTM transmission and point-to-point (PTP) transmission (or changing sub-district), RLC entity 152 is reinitialized.This is can cause any not fully up to expectationsly is arranged in the losing of data of Radio Link control (RLC) buffer.As mentioned above; When travelling carriage when a sub-district moves to another; Or when in the transmission of Serving cell inner multimedia broadcasting and multicast services (MBMS) content when point-to-point (PTP) transmission mode becomes point-to-multipoint (PTM) transmission mode, problem may occur.

Expectation can be in the transition period between point-to-point (PTP) transmission and point-to-multipoint (PTM) transmission; Or the conversion that between different districts, takes place (for example; Handover) during, keep the continuity of multimedia broadcasting and multicast services (MBMS), and expectation can be avoided the submission of duplicate message.For continuity that keeps the MBMS service and the submission of avoiding repetition message, layer 2150 should be able to be arranged the data from two streams again.Thisly can not provide by physical layer synchronously, because internet destination maybe be different in each pattern.If below rlc layer 150, carry out forward error correction (FEC), as the situation among the 3GPP2, any transition period between point-to-multipoint (PTM) transmission and point-to-point (PTP) transmit and then in the reciprocal transition period, may obliterated data.In addition, this will require physical layer synchronization and between a plurality of sub-districts (for example, having public scheduling), share identical medium access control (MAC).Thereby this can cause problem in the inapplicable 3GPP2 of these supposition institutes.

Point-to-point (PTP) transmission

Suppose to use to have significant delay tolerance, then active data transmission mode is Radio Link control (RLC) affirmation mode (AM) for point-to-point (PTP) transmission.For example, RLC affirmation mode (AM) typically is used for the packet switched data transmission (PTP) on the dedicated logical channel.Operation in the affirmation pattern (AM) of RLC on dedicated logical channel.Shown in Fig. 5 A, the private subscribers that upwards is used for user's service at downlink side is professional, can be sent out through the logic channel that is called Dedicated Traffic Channel (DTCH).

In affirmation mode (AM), if data have error code, then reverse link can be used for repeat requests.RLC transport service data unit (SDU), and through retransmitting the transmission that guarantees its peer-entities.If RLC can not correctly transmit data, then the user at the RLC of transmission end is notified.Operation has higher power efficiency usually in RLC AM, and this is a cost to introduce additional delay.

Point-to-multipoint (PTM) transmission

CTCH Common Traffic Channel (CTCH) is the one-way channel that is present in the down link direction, and when sending information at all terminals or specific one group of terminal, can use this CTCH Common Traffic Channel.These data-transmission modes all use the unidirectional common signal channel of not setting up reverse chain channel.

Expectation can provide the structure of a kind of permission MBMS service transparent switching between point-to-point (PTP) and point-to-multipoint (PTM) transmission mode.Obtain good performance during for the conversion between point-to-point (PTP) and point-to-multipoint (PTM) transmission mode, also expect the structure that can provide a kind of permission between different radio controlling links (RLC) pattern, to switch.This can help for example to reduce power requirement.

Now will according to shown and with reference to the embodiment that Fig. 6 to 19 describes, aspect of the present invention is described.These characteristics through using new forward error correction (FEC) layer, especially can help to remain on the service continuity of these transition periods.

Fig. 6 is improved figure with UMTS protocol stack of forward error correction (FEC) layer that can in forward error correction (FECd) pattern and forward error correction (FECc) pattern, operate.Radio Link control (RLC) entity 152 that forward error correction (FEC) layer allows lower floor at subscriber equipment (UE) when point-to-point (PTP) transmission becomes point-to-multipoint (PTM) transmission; Become another kind of Radio Link control (RLC) data-transmission mode from a kind of Radio Link control (RLC) data-transmission mode, keep service continuity simultaneously.According to this embodiment, the FEC layer can be operated in first pattern (FECc) or second pattern (FECd).In an implementation, first pattern (FECc) can be used parity block, and second pattern (FECd) can be operated under the situation of not using parity block.Between FECd and FECc pattern, change to influence meeting more much lower than the influence that between the RLC pattern, changes, and can be seamless, so that do not have loss of data in the transition period.

Forward error correction (FECc) pattern can use the external encode technology to protect user data.This can be effective especially on common signal channel.Forward error correction (FECc) pattern allows on Radio Link control (RLC) layer, to have the function that typically in Unacknowledged Mode (UM), exists, and adds such as framing (segmentation and splicing) and sequence number.As a result, Radio Link control (RLC) layer can use transparent mode (TM) for point-to-multipoint (PTM) transmission, because traditional Unacknowledged Mode (UM) function can be carried out at forward error correction (FEC) layer.Although can control at Radio Link in (RLC) affirmation mode (AM) and duplicate this function and since the gain compensation that ARQ produces this duplicating.

Through being placed on Radio Link control (RLC) layer top to forward error correction (FEC) layer or external encode, can be added in sequence number in the layer that is independent of Radio Link control (RLC).The additional overhead such as sequence number is used in non-affirmation transmission, can during the asynchronous transmission of MBMS data, be arranged protocol Data Unit (PDU) again with encoder packet (EP).Because sequence number is added in the layer of Radio Link control (RLC) top; So sequence number is public in point-to-point (PTP) transmission and point-to-multipoint (PTM) transmission; Therefore when the conversion that is transferred to point-to-point (PTP) transmission from point-to-multipoint (PTM) takes place, can keep the continuity of sequence number.This allows data to be arranged again, so that can avoid the repetition of data and/or losing of data.

Also can in point-to-point (PTP) transmission, use external encode, the delay that this can obtain some power and/or reduce to retransmit for system potentially.Multimedia broadcasting and multicast services (MBMS) data can have delay tolerance to a certain degree.In point-to-point (PTP) transmission, provide feedback path.Owing to use ARQ to retransmit where necessary, make that the use of Radio Link control (RLC) affirmation mode (AM) is more effective, wherein ARQ retransmits more has wireless efficient than the FEC scheme of always sending the additional parity piece usually.Thereby on the dedicated logical channel of for example point-to-point (PTP), it is unnecessary that the MBMS payload data is added parity block.

Fig. 7 A and 7B have shown the embodiment of the protocol architecture of Access Layer, and this Access Layer comprises forward error correction (FEC) layer 157 that places Radio Link control (RLC) layer 150 top.An embodiment of forward error correction (FEC) layer will be described with reference to Figure 11.

Forward error correction (FEC) layer 157 directly receives user plane information 163 through User Plane Radio Bearers.Because forward error correction (FEC) layer is positioned at the top of Radio Link control (RLC) layer, so FEC protocol Data Unit (PDU) is corresponding to RLC service data unit (SDU).The FEC layer is preferably supported: arbitrarily (be restricted to 8 bits many times) SDU size, variable bit rate source, unordered reception are from the grouping of low layer and the reception repeated packets from low layer.Can be restricted to many times of 8 bits to the size of FEC PDU.

As with reference to Fig. 9 A below in greater detail, FEC layer 157 is the higher level user data blocks such as SDU, segmentation and be spliced into the row of equal sizes.Also can call internal block to every row.Each protocol Data Unit (PDU) can comprise expense.Expense can comprise length indicator (LI), and this length indicator indicates the original position of last protocol Data Unit (PDU), from the data of specific user's data block, such as service data unit (SDU), can be positioned like this.The set of PDU comprises encoder packet (EP) or " encoder matrix ".Be included in the numbering of the PDU in the encoder packet (EP), especially depend on the external code that is used.Each encoder " matrix " row be bundled to independently or independent Transmission Time Interval (TTI) in, can strengthen the physical layer performance.In order to reduce the buffering burden, can use short Transmission Time Interval (TTI) duration.

Then, can transmit encoder packet (EP), generate parity rows through the external code encoder.As below will with reference to Fig. 9 A in greater detail; FEC layer 157 can be carried out external encode through the function that Reed Solomon (RS) encoder is provided in UMTS Terrestrial radio access network (UTRAN) 20, and can be through in subscriber equipment (UE) 10, providing the function of ReedSolomon decoder to carry out external decoder.

Can be added to the parity rows that external encoder generates on the encoder packet (EP), and can place it in the transmission buffer as one group of internal block.Each internal block has the information that adds on it, to generate protocol Data Unit (PDU).Can transmit this group PDU then.

FEC layer 157 also allows to recover to belong to the data of single EP, even receive different internal blocks from different sub-districts.This can obtain through in the letter head of each protocol Data Unit (PDU), transmitting sequence number (SN).In one embodiment, System Frame Number (SFN) can help to keep the arrangement of data with respect to encoder packet (EP).For example run through this piece document, discuss sequence number in more detail with reference to Figure 10 A and 10B.

FEC layer 157 is also carried out and is filled and reorganization; The transmission of user data; And the transmission according to the order of sequence of execution upper strata PDU, duplicate detection and sequence number check.

Among the embodiment that in Fig. 6 to 7A, shows; Forward error correction (FEC) layer 157 (for example is displayed between PDCP (PDCP) layer 156 and the Radio Link control (RLC) layers 150; With (BMC) layer at same one deck, and in PDCP (PDCP) layer below).Through just placing forward error correction (FEC) layer 157 Radio Link control (RLC) layer 150 top, the performance of ability optimization external code is because internal block " gold " grouping size big or small and through aerial grouping of sending is complementary.Yet, it should be understood that to show forward error correction (FEC) layer here, only be purpose in order to explain rather than to limit.Can on the top of forward error correction (FEC) layer 157, use PDCP (PDCP) layer 156, to use its letter compressed capability.It should be noted, for point-to-point (PTP) transmission of using dedicated logical channel defines current grouped data convergence protocol (PDCP) layer 156.Shown in Fig. 7 B, can control any position in the Access Layer of (RLC) layer top at Radio Link or forward error correction (FEC) layer is provided in application layer.Forward error correction (FEC) layer can be in the below or the top of PDCP (PDCP) layer.If carry out FEC in application layer 80, then can be applied to it among GSM and the WCDMA identically, size will be different the two for this even " gold " divides into groups.

The external code design

New forward error correction (FEC) layer can be carried out the external encode about user plane information.Fig. 8 is display message piece 91 and the figure of external code piece 95 with explanation external code block structured notion.Fig. 9 A shows the figure that how can be applied to the external code block structure instance in multimedia broadcasting and multicast services (MBMS) data 91.When the content that postpones was tolerated in broadcasting on whole sub-district, external encode can improve the physical layer performance.External code can for example help to avoid in the transition period during the inter-cell transitions and between point-to-point (PTP) transmission mode and point-to-multipoint (PTM) transmission mode, the losing of data.

External code piece 95 can be represented with the form of the matrix that comprises k protocol Data Unit 91 and N-k parity rows 93.Externally in the block encoding; It is capable to be organized into k payload to user data through fill (comprise and being inserted into expense in the internal block) via segmentation, splicing and data; Come to install to data set in grouping of unitary Item device or the block of information 91; Then the block of information 91 that obtains is encoded, to generate N-k parity rows 93, they can be added in the block of information 91 to generate external code piece 95.Parity block 93 is added to redundant information in the block of information 91.Then, the single row in the external code piece finally can pass through single or a plurality of Transmission Time Intervals (TTI) and is transmitted.The redundant information of the set of protocol Data Unit (PDU) can allow raw information to be constructed again, even some PDU are lost during the transmission.

Fig. 9 A has shown the schematic external code structure that is commonly referred to as Reed-Solomon (RS) block code.Reed-Solomon (RS) code can be used for detecting and correcting channel error code.The external code that shows among Fig. 9 A is that (wherein each Reed-Solomon (RS) code sign comprises the information of a byte by the row and column definition for n, k) block code in system.Every row comprise Reed-Solomon (RS) code word.If will recover n the piece of losing, then need n parity block at least.Thereby needed memory space increases with the increase of parity block number.In Reed-Solomon (RS) coding, can be added to N-k parity character on k the system symbol, to generate code word.In other words, the code word [N, k] of Reed-Solomon (RS) code has k information or " system " symbol and N-k parity character.N is the length of code, and k is the dimension of code.For every k information byte, code generates the symbol of n coding, and its preceding k can be identical with information symbol.Can call " internal block " to every row, it representes the payload of every Transmission Time Interval (TTI).In the WCDMA of routine system, transmission can be carried out through the basic WCDMA structure of for example 20ms frame (TTI).The generator matrix G that uses as give a definition _{K * N}, can obtain parity character from system symbol:

G _{1 * k}G _{K * N}=c _{1 * N}(equality 1)

m _{1 * k}=information word=[m ₀m ₁... m _K-1] (equality 2)

c _{1 * N}=code word=[c ₀c ₁... c _N-1] (equality 3)

M wherein _i, c _iBelong to any Galois territory.For example, if the symbol of Reed-Solomon (RS) code word is a bit, then will use the Galois territory (GF (2)) of 2 dimensions to describe decode operation.In one embodiment, if symbol is an eight bit byte, then can use the Galois territory GF (256) of 256 dimensions to describe decode operation.In this case, each information of every row is listed as by 1 byte and forms.Can go up at the Galois territory GF (256) of 256 dimensions and use [N, k] Reed-Solomon (RS) code each information row coding.If every row has the M byte, then external block is encoded M time.Therefore, each external block 95 has the N*M byte.

The deletion decoding

The external code structure allows deletion to correct.If which symbol decoder has known is wrong, then the wrong system symbol of structure needs relatively little amount of calculation again.Encoder packet (EP) or matrix refer to the externally whole set of the data of the output of encoder.To from every row, being removed, and the every row that is transmitted has the CRC that attaches on it to redundant information according to row, and this CRC must correctly be sent to confirm data in verification.Under the situation of MBMS transmission, can in each transport channel block, use CRC, whether this CRC indication internal block 91 is wrong, and if the CRC failure, can suppose that then all symbols in the piece are wrong.In one embodiment, if given internal block is wrong, then can delete all bits that are used for this piece.Term " deletion " refers to each symbol of the erroneous block that belongs to the CRC failure.Can suppose that it is correct not having the symbol of deletion.Ignore CRC and do not detect wrong probability, then each N * 1 row comprise correct and symbol deletion.

The vectorial r that receives can be written as:

r _{1 * N}=[c ₀E e c ₃c ₄E c ₆c ₈... c _N-1] (equality 4)

Wherein e sign deletion.

The deletion decoding allows to correct and is up to N-k mismark.Because can not have the deletion symbol be assumed to correct, so the error-correcting performance of RS sign indicating number is more much better than the error-correcting performance of typical R S sign indicating number usually.The size of the CRC that in each internal block, uses should be enough big, is no more than remaining external block probability with the probability of guaranteeing undetected error code.For example, if in internal block, use 16 CRC, the lower limit of the then remaining external block error rate will be 2 ^-16=1.510 ^-5If in a preceding k internal block, do not have error code, then need not carry out the RS decoding, because system symbol is identical with information symbol.

What can notice is in case receive the k piece with good CRC, just can carry out the decoding of external block, and need not wait for the reception of all N internal block.In order to carry out deletion decoding, can be through removing all and deletion or the unnecessary corresponding row of piece, from generator matrix G _{K * N}The generator matrix Ω that is improved _{K * k}, for example, k the good symbol that receives comes the generator matrix Ω of identification improvement before can only using _{K * k}Available following mode is recovered source information word m:

m_{1 \times k} = {[Ω_{k \times k}]}^{- 1} \cdot r_{1 \times k}^{'}

(equality 5)

R wherein _{1 * k}' be k vector that good symbol obtains before the improved usefulness that receives.Thereby the deletion complexity of decoding can be reduced to the complexity of k * k matrix inversion.Therefore, the computation complexity of RS decoding can be greatly simplified in the use of RS deletion decoding.

Packing data is to the external code Effect on Performance

As below will discussing with reference to Figure 11-13, if limited by the particular outer encoding scheme through the amount of aerial filling of sending and expense, then external encode can use with the variable-speed data source jointly, and does not cause excessive expense.In the external code scheme of discussing, can become piece to packing data in the above, and can on these pieces, operate the ReedSolomon sign indicating number that shortens to sizing.Available at least two kinds will be bundled to the grouped data of coding among the TTI with reference to the different mode of Fig. 9 A and 9B description.

Fig. 9 B is the external code block structured figure of displayed map 9A, and wherein every Transmission Time Interval (TTI) can send multirow.According to a further aspect in the invention, the data from delegation are transmitted in single TTI.In another embodiment, the data of going from an encoder packet (EP) are placed among the TTI, so that each TTI comprises the data from that encoder packet (EP) row.Thereby, can in independent WCDMA frame or Transmission Time Interval (TTI), transmit every row.In a TTI, transmit and whenever be about to provide more performance.In Fig. 9 B, k and n are divided by the line number of every TTI, and the error code in the row can all be associated.When checking the EP error rate and the TTI error rate, this can produce tangible difference.

Fig. 9 C is the outside block structured figure of displayed map 9A, and wherein every row can be sent out in a plurality of TTI.In four TTI (TTI0-TTI3), send every row of encoder packet (EP) though it should be understood that Fig. 9 C diagram, in fact can in the TTI of arbitrary number, send every row.Because every row are external code code words, so each " stage " in four different transmission " stage " (TTI0-TTI3) is equivalent to independently external code.In order to recover whole group, all these independently external codes are necessary correctly to decode.

Figure 10 A and 10B are the figure that shows the external code piece that is generated by the forward error correction layer.

The FECc pattern can be used on public or point-to-multipoint (PTM) logic channel, to construct external condition piece 95 on the MBMS payload data 91 through being added to parity rows or piece 93.Each external block 95 comprises a plurality of internal blocks 91,93.The order of sign internal block and they positions with respect to encoder packet can allow to be placed on each available internal block on the correct position, so that can correctly carry out external decoder.In one embodiment, each internal block comprises through internal block numbering m and external block and numbers the letter 94 that n identifies internal block.For example, external block n comprises having m inner multimedia broadcasting and the data division 91 of multicast services (MBMS) payload block and the redundancy section 93 with the individual inner parity block of M-(m+1).According to this embodiment, can be MBMS optimization serial number space, and available many different sequence numbers define serial number space, for example, 0 to 127.Serial number space should be enough big, so that behind the reception gap that the conversion by any kind of causes, identical sequence number can not occur.Even some pieces are lost, receive the order that UE also should be able to confirm internal block.If the internal block that UE loses is than can be many by the internal block of whole serial number space sign, then UE can not correctly resequence to internal block.The sequence number of same internal block is identical for the FECd piece with the FECc piece.The FECd piece does not comprise the redundancy section 93 that uses in the FECc piece.The FECd entity can use identical aerial bit rate with the FECc entity.

The transmission end

Transmit forward error correction (FEC) entity 410 and comprise service data unit (SDU) buffer 412 that is used to receive SDU; Segmentation and concatenation unit 414; Carry out the external encoder 416 of Reed Solomon (RS) coding; Be added to sequence number the sequence number maker 418 on the PDU that is encoded, transmit transmission buffer 420 and the scheduling unit 422 of PDU through logic channel 406.

Like arrow indication, service data unit (SDU) buffer 412 receives the user data (FEC SDU) on the radio bearer 402 with the form of service data unit (SDU), and storage is from the FEC SDU of higher level.Reception buffer 412 is given scheduling unit 422 transmitting how many data communication.

As discussed above, typically, filling the time quantum that encoder packet (EP) spent will change, because source data rate normally changes.As with reference to Figure 13 explanation,, can improve frame and be full of efficient through determining when begin packing data neatly.Through coming to postpone as far as possible the generation of EP, the loading that can reduce to introduce based on the jitter toleration that receives FEC entity 430.

Scheduling entity 422 can determine when to begin coding.Scheduler program 422 is preferably based on the Qos strategy that is used for that special services, how long confirms before grouping need be sent out, to wait for possibly.In case scheduler program 422 is confirmed to have accumulated enough data, or has exhausted acceptable largest packet propagation delay, scheduler program 422 just triggers the generation of encoder packet (EP) 91.Segmentation and concatenation unit 414 are divided into each row to service data unit (SDU), and generate length indicator (LI).

Scheduling unit 422 preferably determines the optimum line number of EP or protocol Data Unit (PDU), so that SDU can install in the row (for example 12 row) of this number just.Alternatively, scheduler program 422 is from those sizes by the RRC configuration, and the FEC PDU that selection will cause minimum to fill is big or small, and demand staging & splicing function 414 is formatted into the big or small k piece of PDU_size-FEC_Header_size that is to SDU.This format can change.To dissimilar formative instances be discussed with reference to Figure 12-13 below.The data total amount of considering should comprise the expense that adds by splicing and fragmentation feature 414.In order to generate encoder packet (EP), scheduler program 422 request splicings and fragmentation feature 414 generate k that big or small PDU.This big small-scale comprises shuffling information.In one embodiment, PDU can have many times size of 8 bits, and the data of continuous P DU are corresponding with the distinct symbols in the code word.

Then, k PDU piece can be through carrying out the external encoder 416 of Reed Solomon (RS) coding.External encoder 416 comes the data in encoder packet (EP) matrix are encoded through generating redundancy or parity information and appending to redundancy or parity information in encoder packet (EP) matrix to generate the external code piece.In one embodiment, can suppose that external code is (n, n-k parity block of k) deletion decoding block code, and external encoder generation.Encoder is carried out coding on the capable information of the k of equal length, and sends it low sublayer n protocol Data Unit (PDU) of identical size to.It is identical that preceding k piece and its receive, and an ensuing n-k piece is corresponding to parity information.

Scheduler program 422 is gone back the relative timing that Looking Out Time is aimed at or PTM flows, and carries out the aligning of transmission with adjustment Different Logic stream.For example, during reconfiguring, can adjust the time alignment between PTP and the PTM logic flow, to help service continuity.When these streams are synchronous fully, can obtain optimum performance.

Different base stations (or different transmission modes PTP, point-to-multipoint (PTM)) transmits identical content stream, but these streams possibly be out-of-alignment.But the encoder packet of event data stream (EP) form is identical, and then the information on each stream is identical.Subscriber equipment (UE) each external block added sequence number allows subscriber equipment (UE) to make up this two streams, because can be known the relation between these two streams.

Sequence number maker 418 usefulness with in encoder 416 with generating the identical order of order of PDU, be added on sequence number the front of each piece.In one embodiment, the sequence number maker is added in the front of each external code piece to the for example sequence number of 8 bits, to generate PDU.Also can be added to additional overhead information in the external code piece.Serial number space should be enough big, to hold the time difference (time-difference) of the worst condition between these streams.Therefore, in another embodiment, can use 20 serial number space, in each letter head, can keep 5 bits at least and be used for sequence number.After having carried out Reed Solomon (RS) coding, can append to this letter head in the external code piece, so this " outside " letter head does not receive the protection of external block.Also be preferably parity block and add sequence number, even can not transmit them.In one embodiment, the sequence number phase place can with the encoder packet boundary alignment.The reception that the upset of sequence number will be divided into groups corresponding to new encoder.

Forward error correction (FEC) letter form

As mentioned above, comprise through introducing the sequence number of the information relevant obtaining the synchronous of data flow with PDU ordering.Except that rearrangement with the duplicate detection, sequence number allows to be arranged again from the data that are included in the source separately in the encoder packet.This sequence number can identify the order that each grouping should be considered clearly.This sequence number can be formed " FEC head ", should " FEC head " after coding is performed, can be affixed to information payload unit (PDU) and parity block simultaneously.This sequence number should not receive external code protection, because it need be used for decoding.

Figure 14 is the figure of the embodiment of forward error correction (FEC) form.Arrangement for the ease of data with encoder packet (EP); Divisible sequence number is to comprise reserve part (R) 402; The encoder packet (EP) of sign EP is the inner encoder of (EPSN) and the sign position of specific internal piece in encoder packet (IEPSN) 406 that divide into groups partly.

Expectation FEC layer 400 can be operated between all Radio Link control (RLC) patterns.Because Radio Link control (RLC) AM and Radio Link control (RLC) UM require service data unit (SDU) to have many times size of 8 bits, expectation FEC layer 400 also meets this requirement.Because be used for the data recruitment operation of the external code of FEC layer 400 with byte-sized, the size of encoder packet (EP) row also need be the integral words joint.Therefore, the FEC head size 401 that is used for FEC protocol Data Unit (PDU) size also should be many times of 8 bits, accepts so that can be controlled (RLC) by Radio Link.In one embodiment; Forward error correction (FEC) letter 401 can be a byte; Reserve part (R) 402 comprises individual bit, and the part (EPSN) 404 of sign EP comprises 3 bits, and IEP part (IEPSN) 406 of the position of sign PDU in encoder packet comprises 4 bits.In this embodiment, used 8 bit sequence, will send a PDU, and surpassed 100ms because do not expect the transmission drift regularly of different districts because expect each TTI.

Transmit buffer 420 storage PDU up to having accumulated frame data.When PDU is asked, transmit buffer 420 and pass through wave point (Uu) via logic channel, be sent to the MAC layer to frame one by one.The MAC layer is delivered to physical layer to PDU via transmission channel then, and in physical layer, PDU can finally be delivered to UE 10.

Receiving terminal

Still with reference to Figure 11; Receive forward error correction (FEC) entity 430 and comprise reception buffer/rearrangement/repetition detection unit 438; Sequence number is removed unit 436, carries out the outer decoder 434 of Reed Solomon (RS) decoding, and recomposition unit/service data unit (SDU) transmits buffer 432.

The information row of EP matrix is corresponding to PDU.In order to support external encode, received forward error correction (FEC) entity 430 before triggering external decoder, the sequence number of accumulation FEC PDU.In order to obtain continuous reception, although the needs that have pair encoder packet to decode, subscriber equipment (UE) cushions the protocol Data Unit (PDU) that arrives when carrying out decoding.

Divide into groups (EP) before receiving whole encoder, or think at (unshowned) scheduling unit and to die on before the re-transmission of encoder packet (EP) that reception buffer 438 can accumulate PDU.In case decision will can not receive data again for given encoder packet, just can be designated deletion to the PDU that loses.In other words, in decoding processing, will be by the deletion replacement through the PDU of CRC check.

Owing to may lose some pieces during the transmission; And also because different data flow possibly have different delays; So receive forward error correction (FEC) entity 430 in reception buffer/rearrangement/repetition detection unit 438, carry out duplicate detection and possibly carry out rearrangement to the piece that receives.Can in each FEC protocol Data Unit (PDU), use sequence number, with auxiliary rearrangement/duplicate detection.Can in reception buffer 438, use sequence number, so that the unordered data that receive are resequenced.The PDU in case resequenced, repetition detection unit just based on their sequence number, detects the repetition PDU in the encoder packet (EP), and removes any repetition.

Then, can remove these sequence numbers.Sequence number is removed unit 436 and from encoder packet (EP), is removed sequence number, because sequence number cannot be a part that sends to the piece of Reed Solomon (RS) decoder.

Can pass to external decoder function 434 to data then, with the information of recovering to lose.Outer decoder 434 received code devices groupings (EP), and if necessary, Reed Solomon (RS) uses parity information that encoder packet (EP) is decoded, with row any mistake of regenerating or that lose.For example; If all k the protocol Data Units (PDU) that comprise information are not by correct reception; Or be less than k PDU among n PDU not by correct reception, then, can carry out the information PDU of external decoder then to recover to lose for the protocol Data Unit (PDU) of the size of as many as odd even PDU.No matter when carry out external decoder, can obtain at least one odd even PDU at receiver.If all k the protocol Data Units (PDU) that comprise information are correctly received, perhaps be less than k correct reception of PDU quilt among n PDU, then decoding there is no need.Can send recombination function 432 to message protocol data unit (PDU) to then.

Whether successfully irrelevant with external decoder, can send information row to recomposition unit/function 432 subsequently.Recomposition unit 432 is used length indicators (LI), recombinates or constructs the SDU from the information row of encoder packet (EP) matrix again.In case successfully put SDU together, service data unit (SDU) transmits buffer 432 just through radio bearer 440 transport service data units (SDU), to be sent to higher level to SDU.

Receiving forward error correction (FEC) entity 430 places, UE can the permission system be made full use of the time migration between the decoding delay Different Logic stream owing to the unordered reception that lacks the data that possibly exist that cause synchronously between the logic flow.This makes service steadily during the handover and the transition period between PTP and PTM.To discuss with reference to Figure 15 is used to make the UE can be the algorithm of the time migration between the decoding delay Different Logic stream.

Encoder packet (EP) option: fixing or variable row is big or small

FEC or external code entity have flexibility for when constructing protocol Data Unit (PDU), because do not need to send continuously protocol Data Unit (PDU) at each Transmission Time Interval (TTI).This can cause better frame to fill up (frame-fill) efficient and littler filling (padding) expense.

If needed, the external code entity can generate payload at each Transmission Time Interval (TTI).Can construct protocol Data Unit (PDU) in real time, because can receive service data unit (SDU) from higher level.If there are not enough data configuration protocol Data Units (PDU), then RLC can add filling.

The encoder packet (EP) of fixing row size

When decoding SDU 201-204, expectation reduces the amount with the filling that is transmitted as far as possible.

In one embodiment, the capable size of encoder packet (EP) matrix 205 can be a fixed size.The priori of encoder packet (EP) matrix 205 row sizes can allow to return their original configurations to data arrangement.Because the capable size of the SDU 201-204 that is sent out is known in advance, thus can begin to transmit once receiving data, and need not wait for to have checked that how many data will be sent out.

Figure 12 A has shown the instance that is used for generating from data cell 201-204 the decoding processing of external code piece 214, and wherein the capable size of external code piece 214 can be fixed.In this instance, user data adopts the form of a plurality of service data units (SDU) 201-204 of the bit block that comprises any size, and wherein the size of bit block depends on application-specific (video, voice etc.).

In order to transmit the FEC SDU of size arbitrarily, can carry out segmentation, splicing and filling in the FEC level.Although splicing is not strict necessary, lack the remarkable decline that it can cause the higher-layer data throughput.

Higher level SDU 201-204 can at first be formatted into fixing PDU size.In this embodiment, segmentation/splicing function generates the internal block that can be given the fixed size of subscriber unit by indication.In step 220; This group internal block can be by segmentation and splicing, and to become the part of encoder packet matrix 205, this encoder packet matrix 205 comprises internal block; The filling 208 of necessary degree; And length indicator (LI) 206, this length indicator 206 can be used for finishing at the given row of EP through indicating how many SDU, points out the end position of service data unit (SDU) 201-204.The external encoder of discussing below uses these internal blocks to generate redundant block.

In Radio Link control (RLC), length indicator (LI) indicates the end position of each service data unit (SDU), and wherein each service data unit is identified with respect to protocol Data Unit (PDU) rather than service data unit (SDU).This helps to reduce expense, because the PDU size is usually less than the size of service data unit (SDU).For example, length indicator (LI) can be used for indicating last eight bit byte of each the FEC service data unit (SDU) that in payload data unit (PDU), finishes.Can be set as " length indicator ", at the terminal of FEC head be up to the quantity of the eight bit byte between last eight bit byte of FEC SDU section.Length indicator (LI) can be included among the PDU of this length indicator (LI) indication fully.In other words, length indicator (LI) preferably refers to same payload data unit (PDU), and preferably the order with the FECSDU of this length indicator (LI) indication is identical

When receiving external block, can use information such as length indicator (LI), let receiver know service data unit (SDU) and/or the position of filling beginning and finishing.

Owing to can not be in the FEC head come the existence of indicating length designator (LI), so the FEC layer adds the head of fixing of the existence of indicating length designator (LI) in payload with 1 bit.Inner head or LI provide and construct needed all information of SDU 201-204 again.LI can be included among the RLC-PDU of its indication.The existence of the one LI can be indicated by the label in the sequence number head that is included in RLC-PDU.Bit among each LI can be used for indicating its expansion.For the length that allows length indicator (LI) size with FEC PDU changes, the length indicator (LI) that can be a byte is introduced new particular value, lacks a byte with the SDU that indicates previous end and fills last PDU.Length indicator (LI) exists bit to realize in various manners, and wherein two kinds are discussed below.

In one embodiment, can in each protocol Data Unit (PDU), provide length indicator (LI) to have bit.For example, can add a byte at the beginning part of each encoder packet (EP) row, and the existence of the indication of the bit in that byte LI.Can be whole first byte that " there is bit in this " and keeps each protocol Data Unit (PDU).Have bit in order to hold this, the length indicator data can shorten a bit.In each small units (PDU), provide to have bit, allow decoding SDU when EP decoding failure even when a PDU loses.This can cause lower residual BER.In each PDU, provide to have bit, also allow real-time splicing/segmentation.

In another embodiment, can in a PDU, provide length indicator (LI) to have bit.Replacement is added in the beginning part of each PDU to expense, but can be added in the beginning part of first PDU of EP to the bit that exists that is used for all k information PDU.Provide at the beginning part of encoder packet (EP) to have bit, cause the littler expense when having big SDU and/or little PDU.

After segmentation and splicing, EP 205 comprises the row that many at least one by among a plurality of service data units (SDU) 201-204 and filling block occupy.Every row can design the row size of external block, so that can be transmitted with peak data rate during a Transmission Time Interval (TTI).Service data unit (SDU) with the data volume of during Transmission Time Interval (TTI), sending can not be arranged usually embarks on journey.Therefore, shown in figure 11, the second and the 4th SDU 202,204 is not suitable for the Transmission Time Interval (TTI) of first and second row of EP respectively.In this instance, EP has 12 row and can be used for data, and can be grouped into four SDU 201-204 in the first three rows of these 12 row.EP 205 remaining row can be occupied by filling block 208.Like this, can cut apart the 2nd SDU 202, so that the first of second service data unit (SDU) 202 begins at first row of " block of information ", and the second portion of the 2nd SDU 202 finishes in second row.Similarly, Three S's DU must be cut apart, so that the first of the 3rd service data unit (SDU) 203 begins at second row, and the second portion of Three S's DU 203 finishes in the third line.The 4th service data unit (SDU) 204 is contained in the third line, and the remainder of the third line can be full of with filling block 208.In this instance, encoder packet (EP) 213 is mainly formed by filling 208.

Encoder uses EP to generate redundancy or parity information.At step S240, encoder is to encoding through adding the intermediate packets matrix 205 that outside parity block 214 is encoded, and is 16 external code piece 213 to generate length.Encoder extracts 8 Bit datas from every row of each piece, to generate resulting data 210.Reed Solomon (RS) encoder is to resulting data 210 codings, to obtain four lines redundancy or parity information 212.Parity information 212 can be used for generating outside parity block 214, and outside parity block 214 can be affixed to EP matrix 205 to generate 16 external code pieces 213.

Figure 12 B has shown the instance that passes through the aerial information that transmits in the above in the instance of discussing.At step S260, after being added to every row of EP 205 to the additional overhead that comprises sequence number, 16 external code pieces 213 can be used as protocol Data Unit (PDU) 214, through being transmitted in the air.All or whole encoder divide into groups to be transmitted in the protocol Data Unit (PDU) 214 that (EP) 213 matrixes do not send on down link.But protocol Data Unit (PDU) comprises the length indicator (LI) 206 of information bit 201-204 and encoder packet (EP) matrix 213.Because the capable size of encoder packet (EP) 213 is fixed, so this is known at receiver, so there is no need through transmitting filling 208 in the air practically.Filling information 208 does not transmit on down link, because the filling value is known, therefore there is no need to transmit filling information 208.For example, if fill and can form by known bit sequence, such as by complete 0, complete 1 or the bit sequence of 0 and 1 alternating structure form, then receiver can be protocol Data Unit (PDU) the 214 the highest line lengths that are filled into standard coders grouping (EP) 213.Therefore, during transmitting, replace selecting to equal the PDU size of the capable size of EP, can use the obtainable minimum EP size that transmits all information bit 201-204 and reorganization expense 206 (for example LI).

Although encoder matrix row size is fixed, when each transmission, can from given set, select FEC PDU size, so that each FEC PDU comprises all message parts of single encoded device row matrix (filling can be excluded).When receiving size less than the PDU of encoder matrix row size, UE can be with the highest that size that is filled into of known bits sequence.This allows the internal block size to keep fixing, and does not increase the load of air interface.Therefore, use the big or small encoder packet (EP) 213 of fixing row can eliminate and to wait for the obtainable necessity of all data before always, can also eliminate and send the necessity of filling at beginning transport protocol data unit (PDU).

If the algorithm above realizing is handled variable rate transmission, then can use the speed equalization scheme, all encoder packet row matrixs have constant size in the speed equalization scheme.When part PDU has been formed in filling, can use littler PDU.Filling can be made up of specific bit sequence, and can be positioned at the end of data just.At receiver, the big I of the piece that receives from low layer equals baseline (base-line) size through additional filling the endways.

If predetermined bit sequence can be used for filling, then this is not filled and transmits through aerial.Receiver need not known actual encoder packet row size, only if receiver need carry out external decoder.Basic SDU reorganization need not known the terminal loading at PDU.If receive all PDU that comprise from the information of a preceding k encoder packet (EP) row, then external decoder is unnecessary.On the contrary, if at least one PDU that comprises the information of going from a preceding k encoder packet (EP) has been lost, then need at least one to comprise PDU from the data of parity rows.Owing to do not fill parity rows usually, size can be used as the reference of the actual coding device grouping size of needs supposition.

The encoder packet (EP) of variable row size

Figure 13 has shown the encoding process that is used to generate the external code piece 313 with variable row size.

This aspect of the present invention relates to the coding of external block flexibly of the data that transmit through air interface.This encoding process causes still less filling being transmitted, and is full of efficient so that increase frame.The row of encoder packet (EP) 305 can be a variable-size, and can send the external block of different sizes at each Transmission Time Interval (TTI).The row size of encoder packet (EP) 305 preferably changes, in the number row of encoder packet (EP) matrix 305 so that SDU packs into just (for example 12 row).In this embodiment, the FEC layer must wait for that all data can get before structure EP, so that the FEC layer can be confirmed best row size.The big I of row is selected from many different sizes based on the data volume that can get, and fills with restriction.Can be linked to set to the capable size of encoder packet (EP) into the PDU size of S-CCPCH configuration.According to the data volume that can get when generating, can select to cause minimum row size of filling at encoder packet 305 needs.Size through reducing external block 313 can be sent data with the transmission rate that reduces, because send data still less in the duration at identical TTI so that the block size in every frame can be littler.Use the encoder packet (EP) 305 of variable row size, help to stablize power requirement, and use parity overhead 314 still less the transmission of being useful on encoder packet (EP).To point-to-multipoint (PTM) transmission of great use, in the WCDMA system, it is variable that the wireless protocols of lower floor allows the size of the transmission block of transmission in each Transmission Time Interval (TTI) to this embodiment in such as the system of WCDMA.

In step 320, sectional and splicing a plurality of service data units (SDU) 201-204, to generate encoder packet (EP) matrix 305, wherein length indicator (LI) 206 can be used for pointing out the end position of service data unit (SDU) 201-204.Length indicator (LI) can be included in last column, and each service data unit (SDU) terminates in last column.

In step 330, through from each data block, extracting 8 Bit datas, redundancy or parity information are generated by row ground, and resulting data 310 can be sent out the encoder to Reed Solomon (RS), to obtain parity information 312.Because the row of encoder packet (EP) matrix 305 is littler, so can generate redundant information still less.

In step 340, coding is proceeded, because parity information 312 is used to generate outside parity block 314, outside parity block 314 can be affixed to 12 block encoders (EP) matrix 305 that divides into groups, and is 16 external code piece thereby be created on length in this instance.This embodiment has avoided the transmission of filling, and this has improved transmission efficiency, because whole external code piece 313 is occupied by SDU, length indicator (LI) 206 and/or redundant information 314.In this particular instance, do not need to fill.Yet, it should be understood that in some cases, because the number that is configured size of PDU will be limited, and can need some fillings, though will reduce loading.This causes higher frame to be full of efficient, and can allow to stride across whole encoder divide into groups (EP) keep more constant power.This expects in the cdma system that uses power control scheme.

Although not shown, will carry out with being similar to the above mode of discussing about the step S260 of Figure 12 through the transmission of aerial PDU.

Figure 11 has the external encode of RLC Unacknowledged Mode (the UM)+entity (RLC UM+) that on Radio Link control (RLC) layer, provides or the embodiment of forward error correction (FEC) layer 400.Here, the FEC layer that is positioned at Radio Link control (RLC) top is carried out framing.

External encode layer 400 comprises transmission forward error correction (FEC) entity 410, and it is communicated by letter with reception forward error correction (FEC) entity 430 via logic channel 406 through wave point (Uu) 404.

Rearrangement/duplicate detection

Figure 15 is used to make the travelling carriage 10 can be the rearrangement agreement or the algorithm of the time migration between the decoding delay Different Logic stream.

Receiving forward error correction (FEC) entity 430 uses sequence number to confirm the position of the given PDU in the EP matrix.For example, the position of a part of sequence number (PSN) identification PDU in encoder packet (EP).

This algorithm supposition before decoding can be activated, receives the data from two encoder packet (EP) at the most.In the following description, encoder packet (EPd) is to want decoded encoder packet (EP) according to order is next, and encoder packet (EPb) is the encoder packet (EP) that just is being cushioned.Encoder packet (EPb) is followed in encoder packet (EPd) afterwards.Need the full encoder packet delivery time to carry out the UE implementation of RS decoding, needs are carried out double buffering, divide into groups continuously so that can decode.Therefore, the row of the largest amount of n+k at least of UE storage coder matrix (k and n are respectively the numbers and the total line number that comprises parity rows of information row).UE with faster Decode engine can reduce this requirement, although be not less than n+1.For example; If having to exceed based on its decoding capability, UE receives the required a certain amount of buffer space (XtraBffr) of dividing into groups continuously; And if the stream of supposition 64kbps, then at following decoding delay 100ms of the situation that does not increase calculation requirement, will require increases by 800 bytes with buffer sizes.

At frame 1410, can determine whether to receive new forward error correction (FEC) protocol Data Unit (PDU).If do not receive new forward error correction (FEC) protocol Data Unit (PDU), then handle at frame 1410 and restart.If received new forward error correction (FEC) protocol Data Unit (PDU),, can confirm whether new forward error correction (FEC) protocol Data Unit (PDU) belongs to according to order decoded next encoder packet (EPd) then at frame 1420.

If this forward error correction (FEC) protocol Data Unit (PDU) does not belong to according to order decoded next encoder packet (EP); Then, can confirm whether this forward error correction (FEC) protocol Data Unit (PDU) belongs to the encoder packet (EPb) that just is being cushioned at frame 1421.If this forward error correction (FEC) protocol Data Unit (PDU) does not belong to the encoder packet (EPb) that just is being cushioned, then at frame 1440, discardable this protocol Data Unit (PDU).If forward error correction (FEC) protocol Data Unit (PDU) belongs to the encoder packet (EPb) that just is being cushioned really, then at frame 1423, this protocol Data Unit (PDU) can be added in the buffer of EPb at relevant position.At frame 1425, can confirm whether the data volume that is used for EPb has surpassed XtraBffr.Do not surpass XtraBffr if determine the data volume that is used for EPb, then handle at frame 1410 and restart at frame 1426.Surpassed XtraBffr if be used for the data volume of EPb,, transmitted entity and attempt to send complete SDU from EPd then at frame 1428.Then, at frame 1430, the remainder of EPd can be removed from buffer, and at frame 1434, EPb can be set as EPd.

Belong to EPd if determine forward error correction (FEC) protocol Data Unit (PDU) at frame 1420, then at frame 1422, protocol Data Unit (PDU) can be added in the buffer of EPd at relevant position.At frame 1424, can confirm whether buffer has k the independent PDU that is used for EPd.If buffer does not have k the independent PDU that is used for EPd,, handle and restart at frame 1410 then at frame 1426.If buffer has k the independent PDU that is used for EPd really, then at frame 1427, decoder is that EPd carries out external decoder, then at frame 1428, transmits entity and attempts to send the complete SDU from EPd.Then, at frame 1430, the remainder of EPd can be removed from buffer, and at frame 1434, EPb can be sent out to EPd.

Figure 16 shows when travelling carriage is being received from point-to-multipoint (PTM) transmission of sub-district A 99 and between another point-to-multipoint (PTM) transmission of sub-district B99, is changing, by the figure of the time relationship between the external code piece of travelling carriage reception.The people's such as Grilli that some aspects of Figure 16 were submitted on August 21st, 2002 U.S. Patent application US-2004-0037245-A1 and US-2004-0037246-A1 and in the people's such as Willenegger of submission on May 6th, 2002 U.S. Patent application US-2003-0207696-A1, further discussion is arranged, thus they are all quoted as a reference.

Described situation supposition certain UMTS Terrestrial radio access network (UTRAN) 20 and subscriber equipment (UE) 10 requirements.For example, if UTRAN 20 strides the content that the same external block encoding send to be used in the sub-district, then should in adjacent cell, transmit the identical numbering of use on the piece of identical data or payload.External block with identical numbering is transmitted with the mode of time alignment relatively.Striding the peak excursion (misalignment) of the PTM transmission of sub-district is controlled by radio network controller (RNC) 24.The delay jitter that UTRAN 20 controls in point-to-multipoint (PTM) transmission of striding the sub-district.UE 10 should be able to decode to current external block when next external block just is being received.Therefore, the buffer space among the UE should preferably be held at least two external block 95A-95C, accumulates current external block because need be used for the memory of an external block.If external block is in during Reed-Solomon (RS) decoding, memory also should be able to accumulate the internal block of " OK ", with the inexactness of compensation in the time alignment of striding base station 22.

In sub-district A 98, externally during the transmission of piece n 95A, conversion occurs in during the transmission of the second inner multimedia broadcasting and multicast services (MBMS) payload block.96 diagrams of oblique line arrow the conversion of subscriber equipment (UE) 10 A 98 B 99 to the sub-district from the sub-district, oblique line arrow 96 right and wrong levels because passed through some times in the transition period.Till the moment of subscriber equipment (UE) 10 arrival sub-district B 99, the 5th multimedia broadcasting and multicast services (MBMS) payload data just are transmitted.Thereby subscriber equipment (UE) 10 is because the time migration and the transition period elapsed time of corresponding transmission have been lost second to the 4th.If in sub-district B 99, receive enough pieces, then external block n 95A still can be decoded, because can use parity block to come to construct again the piece of losing.

Subsequently, externally during the transmission of piece n+295C, subscriber equipment (UE) 10 experiences another time conversion of B 99 A 98 to the sub-district from the sub-district, and this conversion occurs in the 5th inner multimedia broadcasting and multicast services (MBMS) payload block of external block n+295C.In this case, lost in transition period internal block still less, and still can be recovered external block.

The use of external code piece can help to reduce the possibility of any service disruption.Recover effectively should on each transfer path, send identical piece in order to ensure error code, this means and on each transfer path, to construct parity block in a like fashion.(multimedia broadcasting must be identical on each path with multicast services (MBMS) payload block, transmits because it is broadcasting).Superincumbent application layer 80 is carried out forward error corrections (FEC) and is helped to guarantee that parity block is identical on each transfer path, carries out because be coded in forward error correction (FEC) layer 157, thereby is identical for each external block.On the contrary, carry out, for example carry out, then need some to coordinate, because parity block will be different in each transfer path at the control of Radio Link independently (RLC) entity 152 if be coded in low layer.

Conversion from point-to-multipoint (PTM) to point-to-point (PTP)

Figure 17 shows when the conversion between point-to-multipoint (PTM) transmission and point-to-point (PTP) transmission takes place, by the figure of the time relationship between the external code piece of travelling carriage 10 receptions.The scheme that shows among Figure 17 is applied to for example uses point-to-point (PTP) system for transmitting, such as WCDMA and gsm system.

One aspect of the present invention relates to forward error correction, and it is through adding parity information or piece in inner MBMS " payload " or the data block between the PTM transmission period.Each the external code piece that in the PTM transmission, transmits comprises, at least one inner payload block and at least one inner parity block.The error correcting capability of external code piece can reduce significantly and tend to eliminate in the transition period MBMS perhaps losing of " payload "; This conversion such as when UE when a sub-district moves to another; Or connect when becoming PTP and connecting from PTM when the transmission of MBMS content in same Serving cell, or when rightabout change takes place.

As mentioned above, given sub-district can use PTP or PTM transmission plan to be sent to user 10.For example,, then transmit the sub-district of broadcast service usually with the PTM transmission mode, can select to set up dedicated channel and transmit (only sending certain user 10 to) with ptp mode if the demand to service drops to certain below the threshold value in the sub-district.Equally, go up the sub-district that sends content to each user in dedicated channel (PTP) usually, can determine to be broadcast to a plurality of users to content through common signal channel.In addition, given sub-district can use the PTP transmission mode to transmit content, and identical content can the PTM transmission mode be transmitted in another sub-district.When travelling carriage 10 when a sub-district moves to another, or when the change of the number of users in the sub-district triggers transmission plan and from PTP to PTM, changes or when rightabout changes takes place, change generation.

Externally between the point-to-multipoint of piece n 95A (PTM) transmission period, conversion occurs between the transmission period of the 4th inner multimedia broadcasting and multicast services (MBMS) payload block.101 diagrams of oblique line arrow subscriber equipment (UE) from point-to-multipoint (PTM) be transferred to point-to-point (PTP) transmission conversion, oblique line arrow 101 right and wrong levels because passed through some times in the transition period.When the conversion from PTM 101 to PTP took place, aerial bit rate kept approximate identical.Typically, point-to-point (PTP) transmission has less than centesimal bit error rate (for example, during the transmission, one or error code still less being arranged in per 100 payload block).On the contrary, in point-to-multipoint (PTM) transmission, can suppose higher bit error rate.For example, in one embodiment, per 16 Transmission Time Intervals in base station (TTI) generate an external block, and among these TTI 12 can occupy by payload block, and 4 TTI can be occupied by parity block.The maximum number of tolerable errored block should be 4 internal blocks in 16 (12 basic blocks+4 parity block).Thereby the bLock error rate of tolerable maximum will be 1/4.

When travelling carriage from point-to-multipoint (PTM) transmission conversion 101 when point-to-point (PTP) transmits, some internal block possibly lost.Suppose that point-to-multipoint (PTM) transmission and point-to-point (PTP) are transmitted in physical (L1) and have approximately uniform bit rate; Then the PTP transmission will allow the transmission rate of MBMS payload block to transmit faster than PTM; Because the percentage of the piece that is retransmitted on average, will typically be lower than the percentage of parity block.In other words, point-to-point (PTP) transmission is typically much fast than point-to-multipoint (PTM) transmission, says that statistically the number of parity block is more much bigger than the number that Radio Link control (RLC) retransmits (Re-Tx).Because conversion 101 is to be transformed into much typically fast point-to-point (PTP) transmission from point-to-multipoint (PTM) transmission; So when subscriber equipment (UE) 10 conversions 101 were transmitted to point-to-point (PTP), first of multimedia broadcasting and multicast services (MBMS) payload data just was transmitted.Thereby elapsed time during the time migration of respective transmissions and the conversion 101 does not all cause any lose.Therefore, when moving to point-to-point (PTP) transmission from point-to-multipoint (PTM) transmission,, just can restart through the beginning part simply, come the payload block of compensating missing from current external block in case the PTP link is established at Target cell.Network can begin the PTP transmission through the beginning part from the same external piece, promptly begins to transmit with first internal block, compensates.Owing to the transmission faster of complete external block, network can recover to change the delay of introducing then.Reduce losing of data between transmission period, reduced the interruption that can transmit by the MBMS content that this conversion causes.

Subsequently, externally between the PTP transmission period of piece n+2, subscriber equipment (UE) 10 is exposed to another conversion 103 of point-to-multipoint (PTM) transmission mode.In Figure 12, this conversion 103 from point-to-point (PTP) to point-to-multipoint (PTM) occurs in last inner multimedia broadcasting and multicast services (MBMS) payload block of external block n+2.In this case, except last internal block, many inner multimedia broadcasting among the external block n+2 and multicast services (MBMS) payload block are transmitted.Typically, FEC is used under this situation that can not obtain to feed back.Because dedicated channel is used in the PTP transmission, thereby on reverse link, has feedback capability, so the use of FEC is not useful.In order to minimize or eliminate the loss of data in the cross over transition; UMTS Terrestrial radio access network (UTRAN) 20 preferably relies on the low residual block error rate of RLC affirmation mode (AM) in the PTP transmission, recovers all internal blocks that possibly lost to the transition period of PTM transmission.In other words, common layer 2 retransmits and can be used for retransmitting any grouping that in the transmission of source, is detected error code.Therefore, shown in figure 17, in the PTP transmission, do not need parity block.If between point-to-point (PTP) transmission period, error code is arranged in payload block, decodable code external block still then is because Radio Link control (RLC) layer is with piece of any mistake of request retransmission.That is, when between the PTP transmission period, error code being arranged, travelling carriage 10 or request retransmission (Re-Tx) perhaps when all pieces are correct, do not retransmit, and can use transformat zero (TF0).The layer that external encode is preferably in protocol stack carries out in 2, so that the size of each internal block 97 is packed into just in the Transmission Time Interval (TTI), but because enhance encoding efficient like this.

If forward error correction (FEC) external encode carries out on the upper strata of protocol stack, such as carrying out in application layer, then parity block will be sent out, and no matter be which kind of retransmission scheme (point-to-point (PTP) or point-to-multipoint (PTM)).Thereby parity block also will be affixed in point-to-point (PTP) transmission.

As mentioned above, in the PTP transmission, the use of parity block is optional, because more effective retransmission scheme can replace forward error correction to use.Because parity block is preferably in the PTP transmission and is not transmitted,, suppose identical aerial bit rate so the transmission of complete external block is comparable on average fast in PTM.This allows the UE compensation by the interruption that the conversion of point-to-multipoint (PTM) to point-to-point (PTP) causes, and expects that PTP transmits because can transmit with respect to PTM.Subscriber equipment (UE) can be through the internal block that combines to receive in (1) point-to-point (PTP) transmission in new sub-district or after conversion; (2) internal block that receives in point-to-multipoint in old sub-district or before conversion (PTM) transmission correctly recovers external block.Subscriber equipment (UE) can combine to belong to the internal block that receives before the conversion of same external block and change the internal block that the back receives.For example; Inside multimedia broadcasting among the external block n+2 that subscriber equipment (UE) 10 can combine to receive through point-to-point (PTP) transmission and multicast services (MBMS) payload block and the external block n+2 and inside multimedia broadcasting in the parity block and multicast services (MBMS) payload block that receive through point-to-multipoint (PTM) transmission.UMTS Terrestrial radio access network (UTRAN) 20 can to receiving all users transmission of " expection " external block a little from the MBMS content of PTP link, make things convenient for this processing through with respect to the transmission on the PTM link.

Because transmitting with respect to PTM, UTRAN expects the transmission of external block, so " seamless " from PTP to PTM conversion is possible.As a result, stride cell boarder and/or, also be " seamless " such as the transmission of the MBMS content between the different transmission schemes of PTM and PTP.This " time expection ", the number of available internal block is represented.When subscriber equipment (UE) 10 was transformed into the PTM transmission, even communication link does not exist during change-over time, subscriber equipment (UE) 10 also can be lost the internal block that is up to " time expection " number, and did not damage the QoS that MBMS receives.If directly beginning MBMS in PTP, UE receives; Then UTRAN can use " time expection " at once in the starting point of PTP transmission; Because UTRAN 20 can meet the requirements of the transmission of external block till the internal block of " time expection " number through avoiding sky internal block (TF 0) to come to expect lentamente up to expection.Begin from that, UTRAN can keep constant " time expection ".

In point-to-multipoint (PTM) transmission, can not rely on obtainable UE particular feedback information in the radio network controller (RNC).In point-to-point (PTP) transmission, UE 10 can be the numbering of correct last external block that receives of quilt before conversion, and notice is given RNC.This should be adapted to any conversion (from PTM or from PTP) to PTP.If it is acceptable that this feedback is not thought, then UTRAN 20 can estimate last external block that most probable is received by subscriber equipment (UE) 10 before state exchange.This estimation can based on between the different cell transmission foreseeable maximum time inexactness understanding, and can be based on current just be transmitted or the external block that is about to be transmitted in the Target cell.

Can carry out forward error correction (FEC), so that any of can recover to lose in the transition period.This possibility through reducing can be lost in the transition period content produces " seamless " conversion.The conversion that the supposition of this scheme is transmitted from point-to-point (PTP) to point-to-multipoint (PTM) occurs in identical external block just when each source is transmitted, and this typically occurs in the situation with respect to the duration of the given external block of translation duration.

Memory space among the UE 10 can be compromise with the accuracy in the time alignment of the PTM transmission of striding neighbor cell.Through relaxing the memory requirement in the subscriber equipment (UE) 10, can increase the time accuracy of PTMUTRAN 20 transmission.

Figure 18 is presented at from point-to-point (PTP) transmission of radio network controller (RNC) A with from during the conversion between another point-to-point (PTP) transmission of radio network controller (RNC) B or reorientating, by the figure of the time relationship between the external code piece of travelling carriage reception.Term RNC can exchange with term " base station controller (BSC) " and use.During " reorientating ", subscriber equipment (UE) 10 is transformed into point-to-point (PTP) transmission by the same content stream in the zone of the 2nd RNC B 224 controls from point-to-point (PTP) transmission by the stream of the content the zone of RNC A124 control.Retransmit (re-Tx) and can be used for compensating any MBMS payload block of losing.Soft handover in ' 99 or hard handoff switch can be similar to version, carry out the direct conversion from point-to-point (PTP) to point-to-point (PTP) of minizone.Even without the coordination between two RNC A, the B, Target RNC A 124 also should be able to calculate the nearest whole external block that is received by UE10.This estimation can be based on the moment of the MBMS content that is received by RNC24 on the Iu interface 25.When using the PTP transmission, RNC 24 can compensate initial delay, and even without requiring break-even SRNS to reorientate, also can not lose the partial content of MBMS.

What those skilled in the art may appreciate that is, though for the ease of understanding the flow chart that can sequentially draw, in actual implementation, can carry out some step concurrently.And, only if clearly show, otherwise can exchange method step without departing from the present invention.

This area professional and technical personnel is appreciated that and can uses in a lot of different processes and the technology any one to come expression information and signal.For example, the data of mentioning in the above-mentioned explanation, instruction, order, information, signal, bit, symbol, and chip can be expressed as voltage, electric current, electromagnetic wave, magnetic field or magnetic particle, light field or light particle or above combination.

The professional and technical personnel can also further recognize, the logical block of the example of describing in conjunction with embodiment disclosed herein, module, circuit, and algorithm steps can be performed with electronic hardware, computer software or the combination of the two.For the interchangeability of hardware and software clearly is described, in above-mentioned explanation, has described a plurality of example components, program block, module, circuit prevailingly, reached step according to function.This function can software still be certain applications and the design constraint that hardware mode realizes depending on whole system actually.The professional and technical personnel can use distinct methods to realize described function to each certain applications, but this realization should not be considered to exceed scope of the present invention.

The above combination in any that logical block, module, the circuit of the multiple example of describing in conjunction with embodiment disclosed herein can be used general processor, digital signal processor (DSP), application-specific integrated circuit (ASIC) (ASIC), field programmable gate array (FPGA) or other programmable logic device, discrete gate or transistor logic, discrete hardware components or be designed to carry out function described herein realizes or carries out.General processor can be a microprocessor, but replacedly, processor also can be processor, controller, microcontroller or the state machine of any routine.Processor also may be implemented as the combination of computer equipment, for example, and the combination of the combination of DSP and microprocessor, the combination of a plurality of microprocessors, one or more microprocessor and a DSP core or the combination of other this type of configuration arbitrarily.

Can directly implement in conjunction with the method for embodiment description disclosed herein or each step of algorithm with hardware, the software module of processor execution or the combination of the two.Software module can place the storage medium of any other form known in RAM memory, flash memory, ROM memory, eprom memory, eeprom memory, register, hard disk, removable hard disk, CD-ROM or the technical field.The storage medium of example can be connected to processor, so processor can be from read information and to the storage medium writing information.Replacedly, storage medium can be integrated in the processor.Processor and storage medium can place ASIC.ASIC can place user side.Replacedly, processor and storage medium can be used as separated components and place in the user side.

Above-mentioned explanation to disclosed embodiment makes this area professional and technical personnel can realize or use the present invention.Multiple modification to these embodiment will be conspicuous concerning those skilled in the art, and defined General Principle can realize in other embodiments and can not break away from the spirit or scope of the present invention among this paper.For example; Indicate although describe; Wireless access network 20 can realize through using universal land radio access web (UTRAN) air interface, but alternatively, in the GSM/GPRS system; Access Network 20 can be GSM EDGE Radio Access Network (GERAN), or it can comprise the sub-district of UTRAN air interface and the sub-district of GSM/EDGE air interface under the situation between system.Therefore, the present invention will can not be restricted to these embodiment shown in this paper, but will meet the principle disclosed herein the wideest scope consistent with features of novelty.

The part of file of the present invention openly comprises the material that receives copyright protection.In the time of in it appears at the patent document of patent and trademark office or writes down, the copyright holder does not oppose that anyone is to patent document or the disclosed facsimile copy of patent, no matter otherwise which kind of situation all will keep all copyrights.

Claims

1. method through channel transfering information comprises:

Above wireless chain control layer, make each row framing of first kind information; To generate each row of second type information; Wherein said first kind information comprises that wherein said second type information comprises the payload data of second form through the payload data of first form of radio bearer;

Each row to said second type information above wireless chain control layer is encoded, and comprises each row of the redundant information of parity block with generation;

Said redundant information is appended to after said second type information, comprise first external code piece of each row of the said payload data of the said parity block and second form with generation;

Overhead is added in every row of the said first external code piece, wherein said Overhead comprises sequence number; With

Wireless chain control layer is arrived in the said first external code block movement.

2. the method for claim 1 also comprises:

Reception is from the said first external code piece in first source.

3. method as claimed in claim 2 also comprises:

When the conversion of radio communication device experience; Reception is from the second external code piece of comprising of second source of second grouping identical with each row of said second type information; Each row of wherein said second grouping comprises sequence number; And said conversion is in the following conversion any: the conversion between point-to-point transmission and the point-to-multipoint transmission; Conversion between point-to-point transmission and another point-to-point transmission, the conversion between point-to-multipoint transmission and the transmission of another point-to-multipoint, sub-district internal conversion and inter-cell transitions; With

Use said sequence number to come to aim at again the first external code piece and the second external code piece.

4. the method for claim 1, wherein said second type information also comprises filling information.

5. the method for claim 1; Additional internal block number before coding wherein; Additional external block number behind coding; Allow said wireless chain control layer when the conversion of radio communication device experience, to change pattern, wherein said conversion is any in the following conversion: the conversion between point-to-point transmission and the point-to-multipoint transmission, the conversion between point-to-point transmission and another point-to-point transmission; Conversion between point-to-multipoint transmission and the transmission of another point-to-multipoint, sub-district internal conversion and inter-cell transitions.

6. the method for claim 1, wherein said coding comprises external encode, and is independent of said wireless chain control layer and is performed.

7. the method for claim 1, wherein said channel is unidirectional common logical.

8. method as claimed in claim 7, wherein said channel are unidirectional downlink channel.

9. method as claimed in claim 8, wherein said common logical transmit one or the information of multiple terminals more of being broadcast to.

10. method of giving radio communication device with the first external code piece and the second external code block movement comprises:

Transmit the said first external code piece; The wherein said first external code piece has at least one data line and at least one redundant row that above wireless chain control layer, generates; And wherein every row has the Overhead that comprises sequence number; The said second external code piece only is made up of data line, and wherein each row of the second external code piece has the Overhead that comprises sequence number; With

When said radio communication device experience is changed; Use said sequence number with said first external code piece and the said second external code block alignment; Wherein said conversion is any in the following conversion: the conversion between point-to-point transmission and the point-to-multipoint transmission; Conversion between point-to-point transmission and another point-to-point transmission, the conversion between point-to-multipoint transmission and the transmission of another point-to-multipoint, sub-district internal conversion and inter-cell transitions.

11. a method of passing through channel transfering information that is used for communication system comprises:

Wireless chain control layer is provided; With

The forward error correction layer that places said wireless chain control layer top is provided,

Wherein said forward error correction layer received said first kind information through radio bearer before first kind information arrives said wireless chain control layer;

Wherein said forward error correction layer was the frame of equivalent size with said first kind information framing, to generate second type information before said first kind information arrives said wireless chain control layer;

Wherein said forward error correction layer uses said second type information to generate each row of redundant information, and wherein said redundant information is affixed to said second type information afterwards to generate the external code piece;

Wherein said forward error correction layer added sequence number to every row of said external code piece before transmitting to said wireless chain control layer.

12. method as claimed in claim 11 wherein receives said external code piece from first source, said external code piece is transmitted through common logical.

13. method as claimed in claim 12; Wherein said sequence number allows the external code piece in the transition period; Again arrange with the external code piece from second source, wherein said conversion is any in the following conversion: the conversion between point-to-point transmission and the point-to-multipoint transmission, the conversion between point-to-point transmission and another point-to-point transmission; Conversion between point-to-multipoint transmission and the transmission of another point-to-multipoint, sub-district internal conversion and inter-cell transitions.

14. one kind in comprising the system of wireless chain control layer, before transmitting information, said information is being carried out Methods for Coding through common signal channel, comprising:

Reception is from the said information of radio bearer;

Before said information is passed to wireless chain control layer, said information is carried out the external block coding;

Wherein said information comprises content, and wherein the external block coding comprises:

Said content is organized into data block;

The said data block of encoding is to generate parity block;

Parity block is appended to after the data block, and to generate encoder packet, wherein said parity block is configured to, and is used for constructing again any data block of losing during the transmission; With

Overhead is added among every in the said encoder packet, and said encoder packet is discerned every through comprising the sequence number of internal block numbering and external block numbering, and wherein said Overhead comprises sequence number.

15. method as claimed in claim 14 wherein transmits every in single frame.

16. method as claimed in claim 14 wherein transmits every in a plurality of frames.